phan biet danh dong tu va hien tai phan tu

3. Comparing Gerunds and Participles
3.1 Difference
Gerunds and participles often look similar; they are both verb
forms that end in -ing, but serve different functions in English
grammar. A gerund serves as a noun while a participle serves as
an adjective. And because the same word can often be either a
participle or a gerund, to identify a word's role, you must
examine how it is being used.
3.2 Tricks to identify difference
Look for the Subject
Generally, if a possible gerund can be shown not to act as a
modifier, then you can deduce that it is functioning as a noun
and therefore is a gerund. More specifically, if the possible
gerund functions as the entire subject of the sentence and does
not take any additional punctuation, it is a gerund. For example,
in the sentence, "Setting the table is necessary before dinner,"
"Setting the table" is the subject and takes no punctuation;
"setting" is a gerund.
Look for Participial Phrases
Because gerunds often serve as subjects, they are often
confused with participial phrases at the beginnings of sentences.
Two defining qualities of a participial phrase are the presence of
punctuation that sets it apart from the rest of the sentence, and
the phrase itself, which modifies the subject instead of being the
subject. In the sentence, "Unsheathing his sword, the knight
stormed the castle," "Unsheathing his sword" is a participial
phrase because it is set off by a comma and modifies the subject,
"the knight."
Is It an Adjective?

Sometimes participles function as adjectives, and so another
way to tell that a word is a participle and not a gerund is to
identify it as a modifier, which often precedes the noun it
modifies. Consider the following example: "She offers stinging
criticisms." Here, the word "stinging" serves as an adjective by
modifying "criticisms," and in no way functions as a noun; it is
clearly a participle.
Is It Being Modified by an Adverb?
Sometimes a word in adverbial form will be attached to a
potential participle/gerund, signifying its use as an adjective, and
is therefore a participle and not a gerund. In the sentence:
"Quietly muttering to himself, John struggled through the test,"
the adverb "quietly" modifies "muttering," signalling the identity
of "muttering" as a participle.
3.3 Check out these examples:
Jamming too much clothing into a washing
machine will result in disaster.
Jamming too much clothing into a washing machine = gerund
phrase, the subject of the verb will result.
Jamming too much clothing into the washing
machine, Aamir saved $1.25 but had to tolerate the
curious stares of other laundry patrons as his machine
bucked and rumbled with the heavy load.
Jamming too much clothing into the washing machine =
present participle phrase describing Aamir.
Bernard hates buttering toast with a fork .
Buttering toast with a fork = gerund phrase, the direct object of
the verb hates.

Buttering toast with a fork , Bernard vowed that he
would finally wash the week's worth of dirty dishes
piled in the sink.
Buttering toast with a fork = present participle phrase
describingBernard.
My dog's most annoying habit is hogging the middle
of the bed.
Hogging the middle of the bed = gerund phrase, the subject
complement of the linking verb is.
Last night I had to sleep on the couch because I found
my dog Floyd hogging the middle of the bed .
Hogging the middle of the bed = present participle phrase
describingFloyd.