giao an tieng anh 6

Week: 6
Period: 18 Unit 3: AT HOME
PD: Section B: 3, 4, 5
TD
I.AIMS
By the end of the lesson, students will be able to:
+ Practice the structure: How many……. Are there?
+ count the items in a picture
II. PREPARATION
- teacher: tape, cassette player, pictures
- students: prepare the lesson at home
III. TECHNIQUES: pairs, groups, questions, answers
IV. TEACHING AIDS: tape, cassette player, pictures
V. PROCEDURE
1. Checking attendance
2. Check the previous lesson
Count from 1 to 100
3. New lesson
ACTIVITIES CONTENT
1. warm up
- play game: chain game
- teacher begins with: “ in my
class, there is a teacher”-
students cotinue
2. presentation
- ? how many board are there in
our class?
- Teacher introduces
- Students listen to the tape
- Choral repetition
- Pairswork: practice asking and

answering about things in the
classroom
3. practice
- groupswork: ask about their
friends’ school things
- group/ pair: count the items in
the textbook
- use the structure to ask about this
picture
• There are+ plural nuoun
Ex: There are four windows
There is+ a(n)+ singular noun
Ex: There is a teacher
4. cosolidation
Play game: lucky number
There are 8 number:
1. 2. 3. 4.
5. 6. 7. 8.
Lucky number are: 3, 5, 7
1. How many lamps are there in your classroom?
2. Make a question with “ how many…”
4. How many boys are there in your class?
6. Count the schoolbags in your classroom
8. How many teacher are there in your class?
5. homework
- practice at home
- prepare: C12
6. changes
……………………………………………………………………………………
……………………………………………………………………………………

……………………………………………………………………………………
……………………………………………………………………………………
…………………….
Week: 6
Period: 17 Unit 3: AT HOME
PD: Section C: My family(12)
TD
I.AIMS
By the end of the lesson, students will be able to:
+ Read and understand the text
+ Talk about family and job
II. PREPARATION
- teacher: tape, cassette player, pictures
- students: prepare the lesson at home
III. TECHNIQUES: pairs, groups, questions, answers
IV. TEACHING AIDS: tape, cassette player, pictures
V. PROCEDURE
1. Checking attendance
2. Check the previous lesson
Count from 1 to 100
3.New lesson
ACTIVITIES CONTENT
1. warm up
- students lookat the picture and
guess who they are, what are
they doing, what their names are
2. presentation
- hand out some materials : reorder
the sentences
- 1. he is forty

- +this is my father
- +he is an engineer
- 2. she is a teacher
- + she is thirty five
- + this is my mother
- 3. he is a student
- + my brother is 8 years old
- Gets feedback
- Students listen to the tape
- Choral repetition
- Ex plain some new words
- Some students read the answer
key for the exercise
- Play game: divide class into 4
groups
- Play luckynumber

@ vocabulary
- family (n): gia đình
- father (n):
- mother (n)
- brother (n)
- engineer (N)
- his
- her
- he
- she
There are 12 numbers with 4 lucky
numbers
1. 2. 3. 4.

5. 6. 7. 8.
9. 10 11 12
( lucky number: 2,4,6,8)
The other:
1. how are you?
4. how old are you?
5. what is your name?
7. where do you live?
9. how do you spell your name?
10. count from 1 to 20
11. how many people are there in
tyour family?
12. how old is your father?
- teacher and the whlole class
remark and correct
- after doing the exercise, get
students to tell the meaning of
the question “what does he/ she
do?”
- guide them
3. practice
- groups: ask and answer about
their friends’ family.
- Ask and answer about Song’s
family
• What does she do?
• What does he do?
He/ she a(n)……
Ex: what does ahe do?
She is a teacher

4. consolidation
- question to ask about job
- prepare: grammar practice
5. homework
- practice at home
- preapare: grammar practice
6. changes
……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
……………………
Week: 6
Period: 18 GRAMMAR PRACTICE
PD:
TD
I.AIMS
By the end of the lesson, students will be able to:
- review what they have learn
- do more exercise
II. PREPARATION
- teacher: tape, cassette player, pictures, sub- board
- students: prepare the lesson at home
III. TECHNIQUES: pairs, groups, questions, answers
IV. TEACHING AIDS: tape, cassette player, pictures, sub- board
V. PROCEDURE
1. Checking attendance
2. Check the previous lesson
- what does your mother do?
- what does your father do?

- what do you do?
3.New lesson
ACTIVITIES CONTENT
1. Activity 1
- work in pairs: practice introduce
themselves and their families
- fill in the blanks
- write their answer on the board
- remark and correct
2. activity 2
- reacher does some actions and
gets students to say the
imperatives
- students fillin blanks
- write their answer on the board
- correction
- review the structure “how
many…”
- pairswork: ask ans answer about
things in the classroom
- review some wuestions
- read the question aloud
- correction

1) am- am
are- are
is
are
2) am –is
is- are

are
3) are/ am
is/ is
4) is/ isn’t
are/ aren’t
a. up
b. down
c. Your
d. Your
e. up
3. practice
taecher asks, students answer
4. consolidation
- to be
- imperatives
- how many…?
- question mark
5. homework
- do exercise at home
- reaview what they have learnt
- preapare:45 minutes test
6. changes
……………………………………………………………………………………
……………………………………………………………………………………
…….........
Week: 6 --Period: 18 45 MINUTES TEST
PD: TD:
I. AIMS
To help students review what they have learnt and check their knowledge.
II. TEST

I. Circle the coreect answer.
1. This is Paul. …… teacher from France.
a. He’s a b. He’s an c. He is d. a
2.What’s ……. name?
a. he’s b. his c. the is d. he
3. Hello, Mary. How are you? ……….. thank you, and you?
a. I’m allright b. I’m good c. I’m healthy d.Fine
4. ………….do you spell your name?
a. By how b. What c.How d. What way
5. Where do you live?
a. I live at 23 Le Loi Street b. I live on 23 Le Loi Street
c. I live in 23 Le Loi Street d. I live to 23 Le Loi Street
6. What are these? They …… lamps.
a. is b. am c. are be
II. Write the words under the numbers
59 32 98 100 27 46 87 75
III.Write the questions
Ex: This is my classroom
Is this your classroom?
1. This is my bag.
………………………………………………………
2. This is my school.
………………………………………………………
3. That is my teacher.
………………………………………………………
4. That is my desk.
………………………………………………………
IV. Read the passage and answer the questions.
Hi, my name is Ba. I’m twelve years old. I’m a student. This is my father. His
name is Ha. He is a teacher. He is forty years old. This is my mother. Her name is

Nga.she is a teacher, too. She is thirty- five years old. This is my sister, Lan. She
is a student.she is fifteen years old. I’m her brother.
@ questions
1. How old is Ba?
2. How old is his father?
3. What does his mother do?
4. How old is his sister?
Week: 7
Period: 19
PD: TEST CORRECTION
TD:
I.AIMS
By the end of the lesson, students will be able to:
- correct their 45 minutes test
II. PREPARATION
- teacher: test, textbook
- students: prepare the lesson at home
III. TECHNIQUES: pairs, groups, questions, answers
IV. TEACHING AIDS: test, textbook
V. PROCEDURE
1. Checking attendance
2. Check the previous lesson
3.New lesson
ACTIVITIES CONTENT
1. circle the best answer
- what do you do in this part?
- Ask student to choose
- Why did you choose them?
2. write the numbers
- how to write a number

- how did you write the number?
- Write the number on the board
3. write the question
- how to make questions with “
this is…/ That is…….”
- How did you write the question
- Write the question on the board
IV. answer the questions
- read the text again
- how to manswer the questions?
- Write the answers on the board
I.
1. a
2. b
3. d
4. c.
5. a
6. a
II.
1.fifty nine
2. thirty two
3. ninety eight
4. one hundred
5. twenty seven
6. forty six
7. eighty seven
8. seventy five
III.
1. Is this your bag?
2. Is this your school?

3. Is that your teacher?
4. Is that your desk?
IV. Answers
1. he is twelve years old.
2. he is forty years old.
3. she is ateacher.
4. she is fifteen years old.
4. consolidation
5. homework
6. changes
……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
…………………….
Week: 7
Period: 20
PD: UNIT 4: BIG OR SMALL?
TD: Section A: Where is your school?(A12, B4)
I.AIMS
By the end of the lesson, students will be able to:
- ask and answer about position
- ask and answer about chractreristics
- use possessive of noun
II. PREPARATION
- teacher: textbook, tape, cassette layer, pictures
- students: prepare the lesson at home
III. TECHNIQUES: pairs, groups, questions, answers
IV. TEACHING AIDS: textbook, tape, cassette layer, pictures
V. PROCEDURE

1. Checking attendance
2. Check the previous lesson
3.New lesson
ACTIVITIES CONTENT
1. warm up
- teacher hangs the two pictures of
Phong and thu’s school
- ask students ri find the
differences between them
- remark and lead in
2. presentation
- teacher uses apicture and
introduce: this is Phong’s school
- teacher uses real things and
introduce: “this is Thu’s pen,
these are Nga’s pencils”
- gets students to find the
formation
- Teacher uses picture to introduce
the word “ big”, “small”
FORM: tên ng ười’s+ danh từ(dùng để
chỉ sự sở hữu của người nào đó)
(của……)
Ex: nam’s book
Tan’s father
Thu’s mother
- students listen to the tape
- explain some new words
- listen and repeat
- explain the structure

- studeys read the text in groups
- fill in the blanks
- correction
- groupswork: answer the question
in the textbook
- write their answer on the board
- remark and correct
- students listen to B4
- listen and repeat

@ New words
- country( n)
- in the counrtry
- city( n)
- in the city
STRUCTURE
Am
Is + S + Adj?
Are
It’s +Adj
Ex: is your school big?
It’s small.
1. Thu’s school is……
2. Phong’s school is….
3. …… is in the city
4. …….is in the country
@ Answer
1. Yes, it is
2. no, it isn’t
3. it is in the country.

4. no, it isn’t. it is in the city.
1
st : first 6th: sixth
2nd : second 7th : seventh
- guide them how to read ordinal
numbers from first to tenth
3.practice
talk about their own school
3rd : third 8th : eighth
4th : fourth 9th : ninth
5th :fifth 10th: tenth
4. Consolidation
- adjectives
- possessive
5. Homework
- practice at home
- make question at home
- preparation
6. Changes
……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
…………………….
Week: 7
Period: 21
PD: UNIT 4: BIG OR SMALL?
TD: Section A: Where is your school?(A34, B5)
I.AIMS
By the end of the lesson, students will be able to:

- ask and answer about quantities
- fill in blanks with suitable words
II. PREPARATION
- teacher: textbook, tape, cassette layer, pictures
- students: prepare the lesson at home
III. TECHNIQUES: pairs, groups, questions, answers
IV. TEACHING AIDS: textbook, tape, cassette layer, pictures
V. PROCEDURE
1. Checking attendance
2. Check the previous lesson
- make possession: Tan/ pens
- ? where is your school?
- Is your school big?
3.New lesson
ACTIVITIES CONTENT
1. warm up
- how many windows are there
in our class?
- How many students are there?
- How many desk are there?
2. presentation
- students listen to the tape
- new words
- groupswork: complete the
table
- write their answer on the board
- correction
- pairswork: answer the
questions
- write their answer on the board

- correction
3. practice
- work in pairs and answer these
questions
- ask and answer in front of the
class
@ New words
a. There are eight classroom in
Phomg’s school.
b. There are four hundred
students in his school.
c. There are twenty classroom
in thu’s school.
d. There are nine hundred
students in hre school.
1. is your school in the city or in the
country?
2. how many classrooms are there in
your school?
3. how many students are there in
your school?
4. Consolidation
How many+ plural noun+ are there?
There are+ number
5. Homework
- practice asking and answering at home
- prepare: B123
location classroom
Number
of

students
Phong’s
school
Thu’s
school
6. changes
……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
……………………
Week: 8
Period: 22
PD: UNIT 4: BIG OR SMALL?
TD: Section B: My class(1235)
I.AIMS
By the end of the lesson, students will be able to:
- Ask and answer about their class
- Describe their school
- Fill in blanks with suitable words
II. PREPARATION
- teacher: textbook, tape, cassette layer, pictures
- students: prepare the lesson at home
III. TECHNIQUES: pairs, groups, questions, answers
IV. TEACHING AIDS: textbook, tape, cassette layer, pictures
V. PROCEDURE
1. Checking attendance
2. Check the previous lesson
? How many students are there in your class?
? How many classroom are there in your school?

3.New lesson
ACTIVITIES CONTENT
1. warm up
- students lok at the picture and
guess what they are talkinga
bout
- teacher introduce the content of
their conversation
2. presentation
- students listen to the tape
- who are the speakers in this
conversation?
- Get students to complete the
Grade Number
of floor
Classroom
location
table
- Students work in groups and
complete it
- Write their answer on the board
and fill the number
- Remark and correct
- Pairswork: practice the
dialogue
- Roles play
- Remark and correct their
pronunciation
- New words
- Students complete the chart in

the textbook
- get students to write three
sentences about themselves
- write their sentences on the
board
- pairswork: complete the
dialogue
- read their answer aloud
- correction
Thu
Phong
@ New words
- grade(n)
- Floor(n)
- Have(v)
- isn’t
- does
- has
- are
- am
- is
- on
4. consolidation
- which grade are you in?
- which class are you in?
5. Homework
- practice the dialogue at home
- prepare: C123
6. changes
……………………………………………………………………………………

……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
…………………….
Week: 8
Period: 23
PD: UNIT 4: BIG OR SMALL?
TD: Section C: Getting ready for school(123)
I.AIMS
By the end of the lesson, students will be able to:
- use ordinary verbs with third person
- ask and answer about evryday routine
II. PREPARATION
- teacher: textbook, tape, cassette layer, pictures
- students: prepare the lesson at home
III. TECHNIQUES: pairs, groups, questions, answers
IV. TEACHING AIDS: textbook, tape, cassette layer, pictures
V. PROCEDURE
1. Checking attendance
2. Check the previous lesson
? How many students are there in your class?
? How many classroom are there in your school?
3.New lesson
ACTIVITIES CONTENT
1.warm up
- students talk about what they do
every morning
- look at the picture and talk about
what the boy does every morning
2. presentation

- students listen to the tape
- listen and repeat
- teacher explains some new words
- read the wods in choral
- teacher give some sentences and
get students to tell the differences
@ New words
- get up (v)
- get dreesed
- brush (v)
- teeth (n)
- wash( v
- face (n)
- have breakfast
+ eat breakfast
- go to school
- I go to school by bus
- He goes to achool by bus
beetween them
- ? why do they have these
differences?
- Teacher explains the new
structure
- Give cues and get students to
write the sentences
- Pairs work: do the task and
compare their answer qith each
other
- Make questions with “ what do
you do every morning?”

- Groupswork: ask and answer
with their friends
- Some students ask answer in
front of the class
- Teacher gives “he” and gets
students to make quetions
- guide them how to make
wuestion with third person
- pairwork: ask answer about Ba
- play their role in front of the
class
3. practice
- ask and answer about everyday
routine
- I wash my face
- She washes her face
FORM :
I
They + V (bare inf)
We
You
Lan and Nga
My father and mther
Ex: I get up
They get up
He
She + V(s, es)
It
Lan
My mother

Ex: He washes his face
My mother gets up
• Note: Verbs end with: - o, -sh,
-ch, - x, - ss + “es”.
• The other + “s”
4. consolidation
- ordinary verbs with third person
- talk about evryday routine
5. homework:
- practice at home
- learn the strusture by heart
- preapare: C4567
6. changes
……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
…………………
Week: 8
Period: 24
PD: UNIT 4: BIG OR SMALL?
TD: Section C: Getting ready for school (4567)
I.AIMS
By the end of the lesson, students will be able to:
- Ask and answer about time
- Ask answer about what they do everuday
II. PREPARATION
- teacher: textbook, tape, cassette layer, pictures, clock
- students: prepare the lesson at home
III. TECHNIQUES: pairs, groups, questions, answers
IV. TEACHING AIDS: textbook, tape, cassette layer, pictures, clock

V. PROCEDURE
1. Checking attendance
2. Check the previous lesson
- teacher give sentences and get students to make sentences with third person
- I get up at 6 o’lock(he)
- we go to school at 6.30(she)
3.New lesson
ACTIVITIES CONTENT
1.warm up
- students look at the picture and
guess what they are talking
about, what time it is, are they
late for school
2. presentation
- students listen to the tape
- listen and repeat
- teacher explains how to say the
time
- teacher uses a clock and guide
students how say the time
- teacher gives time and get
students to tell the time
• Giờ hơn:
It’s + phút + past+ giờ
Ex: It’s twenty past nine
It’s half past ten
- pairswork: ask and answer a bout
the time
- play roles
- teacher giude them how to ask

what other person do with “ what
time...?”
- students read the sentences and
then answer the questions in
groups
- write theirs answer on the board
- remark and correct
- work indidually: answer the
questions about themselves
- write their answer on the board
- remark and correcic
3 . practice
- ask and answer about time
• Giờ kém
It’s + phút + to+ giờ
Ex: It’s ten to eight
It’s fifteen to seven
@ Questions
1. What time does Ba get up?
2. what time does he have
breakfast?
3. what time does he go to school?
4. consolidation
- ask and answer about time
- make questions with “ what time…?”
5. homework:
- practice at home
- learn the strusture by heart
- preapare: unit 5: A12
6. changes

……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
……………………
Week: 9
Period: 25
PD: UNIT 5: THINGS I DO
TD: Section A : My day(12)
I.AIMS
By the end of the lesson, students will be able to:
- use ordinary verbs with third person
- ask and answer about evryday routine
- make questions with “ wh”
II. PREPARATION
- teacher: textbook, tape, cassette layer, pictures
- students: prepare the lesson at home
III. TECHNIQUES: pairs, groups, questions, answers
IV. TEACHING AIDS: textbook, tape, cassette layer, pictures
V. PROCEDURE
1. Checking attendance
2. Check the previous lesson
? what time do you get up?
? what time do you have breakfast?
? what time do you go yo school?
3.New lesson
ACTIVITIES CONTENT
1.warm up
- students talk about what they do
every morning / afternoon/

evening
- look at the picture and talk about
what the girl does every day
2. presentation
- students listen to the tape
- listen and repeat
- teacher explains some new
words
- read the wods in choral
@ New words
- every
- play (v)
- games(n)
- do (v)
- homework(n)
+ do homework
- everyday
- every morning
- a student plays the role of Lan,
another is the speaker
- read the sentences in front of the
class
- correct their pronunciation and
intonation
- groupswork: fill in blanks:
- get feedback
- correction
- teacher give the correct answer.
- Teacher ask students about what
they do in the morning,

afternoon, evening
- Then, ask about Nga.
- Students work in groups: ask ans
answer about Nga
- Ask and answer in front of the
class
- Teacher ask asutdent to read the
answer, another write the answer
on the board, then teacher correct
their grammar.
3. practice
Ask answer about what their friends
do in the morning, afternoon,
evening
- every afetrnoon
- every evening
1. Lan ….. up at six
2. she goes to school in the…..
3. she…… in the afternoon.
4. she does her homework in the….
4. consolidation
- ask answer about what others do everyday
5. homework:
- practice at home
- preapare: 34
6. changes
……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
……………….

……………………………………………………………………………………
……………………………………………………………………………………
………………
Week: 9
Period: 26
PD: UNIT 5: THINGS I DO
TD: Section A : My day(34)
I.AIMS
By the end of the lesson, students will be able to:
- ask and answer about what their friends do after school
- make questions with “ wh”
II. PREPARATION
- teacher: textbook, tape, cassette layer, pictures
- students: prepare the lesson at home
III. TECHNIQUES: pairs, groups, questions, answers
IV. TEACHING AIDS: textbook, tape, cassette layer, pictures
V. PROCEDURE
1. Checking attendance
2. Check the previous lesson
What do you do in the morning / afternoon/ evening?
3.New lesson
ACTIVITIES CONTENT
1.warm up
- students talk about what they do
- look at the picture and talk about
what the girl does every day
2. presentation
- students listen to the tape
- listen and repeat
- teacher explains some new words

- read the wods in choral
- a student plays the role of Lan,
Ba, Nam, and Thu, another is the
speaker
- read the sentences in front of the
class
@ New words
- After school
- Watch(v)
+watch television
- do(v)
+ do the housework
- listen(v)
+ listen to music
- read(v)
- correct their pronunciation and
intonation
- groupswork: fill in blanks:
- get feedback
- correction
- teacher give the correct answer.
- Teacher ask students about what
they do in the morning,
afternoon, evening
- Then, ask about Nga, Nam Lan
and Thu
- Students work in groups: ask ans
answer about Nga Nam Lan and
Thu
- Ask and answer in front of the

class
- Teacher ask asutdent to read the
answer, another write the answer
on the board, then teacher correct
their grammar.
3. practice
Ask answer about what their friends
do after school
Ak and write the answer about Lan,
Thu, Nam, and Ba in their exercise
book
5. Lan ….. the housework
6. thu………
7. Ba ……..
8. Nam……. to music
4. cosolidation
- what do you do after school?
- what does Lan do after school?
- what does Thu do after school?
- what does Ba do after school?
- what does Nam do afetr school?
5. homework
- practice at home
- prepare: A56
6. changes
……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
……………………..

Week: 9
Period: 27
PD: UNIT 5: THINGS I DO
TD: Section A : My day(56)
I.AIMS
By the end of the lesson, students will be able to:
- ask and answer questions with ordinary verbs
- yes/ no quesyion
II. PREPARATION
- teacher: textbook, tape, cassette layer, pictures
- students: prepare the lesson at home
III. TECHNIQUES: pairs, groups, questions, answers
IV. TEACHING AIDS: textbook, tape, cassette layer, pictures
V. PROCEDURE
1. Checking attendance
2. Check the previous lesson
What do you do after school?
What does Nga do afetr school?
What does Nam do after schooL
What does Thu do after school?
What does Ba do after chool?
3.New lesson
ACTIVITIES CONTENT
1.warm up
- students talk about what they do
- look at the picture and talk about
what the girls do.
2. presentation
- students listen to the tape
- listen and repeat

- teacher explains some new
words
- read the wods in choral
@ New words
- play(v)
- volleyball(n)
- soccer(n)
- pairs work: practice the dialogue
- roles play
- correct their pronunciation and
intonation.
- Teacher explains the structure
with yes/ no question
- teacher ask some questions and
get student to answer
- pairwork: ask ans answer about
themselves and their friends
- play the roles in front of class
- remark and correct
3. practice
- listen to the tape and answer Yes, I
do or No, I don’t
Structure
DO/ DOES+ S + V +O?
Yes, S+ do/ does
No, S+ don’t/ doesn’t
Ex: doyou play soccer?
Does he play volleyball?
4. cosolidation
- do you play soccer?

-do you play volleyball?
5. homework
- practice at home
- learn the structure by heart
- prepare: B123
6. changes
……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
……………………..
Week: 10
Period: 28
PD: UNIT 5: THINGS I DO
TD: Section B: My routine(123)
I.AIMS
By the end of the lesson, students will be able to:
- ask and answer about someone’s routine
- ask and answer about timetable
II. PREPARATION
- teacher: textbook, tape, cassette layer, pictures
- students: prepare the lesson at home
III. TECHNIQUES: pairs, groups, questions, answers
IV. TEACHING AIDS: textbook, tape, cassette layer, pictures
V. PROCEDURE
1. Checking attendance
2. Check the previous lesson
- Do you play soccer?
- Do you play volleyball?
3.New lesson

ACTIVITIES CONTENT
1.warm up
- students look at the picture and
talk about what the boy is doing(
they guess)
2. presentation
- students listen to the tape
- listen and repeat
- teacher explains some new
words
- read the wods in choral
@ New words
- shower(n)
+ take a shower
- eat(v)
- a quarter
- class(n)
- from…. To…
- lunch(n)
+ have lunch
- go home
- go to bed