Page 86 - Just Enough English Grammar Illustrated Book

I am
swimming.

I am . We are celebrating.

Helping Verb Present Participle Helping Verb Present Participle
(Main Verb) (Main Verb)
To form the present participle, you start with the base form of a
regular or irregular verb. However, there are several spelling
changes to keep in mind:
Add -ing to the base form of the verb: walk ~ walking.
If a verb ends in a silent -e, drop the final -e and add -ing:
write ~ writing.
In one-syllable verbs, the final consonant is often doubled:
swim ~ swimming.
Do not double the consonants w, x, or y: play ~ playing.
Swimming and celebrating are examples of present
participles. Present participles don’t change when they connect
to am, are, and is. They are not able to stand alone, but they
are connected to a form of the helping verb to be.

A verb may consist of more than one word. A main
verb and a helping verb together form a verb phrase.

The following two charts contrast past forms (Principal Part )
with present participles (Principal Part ). Past forms of verbs
stand alone as one word, while present participles (the -ing
form) need a helping verb. It is the helping verb that connects
to the subject and changes according to the subject. The present
participle is the main verb, and it doesn’t change.
3 3 Present Participle
2 Past Form
Subject Helping Present
Subject Pronoun Past Form Pronoun Verb Participle
1 I 1 I am
you you are
2 2
3 he, she, it 3 he, she, it is
un)
(or Singular Noun) (or Singular Noun) walking
walked
1 we 1 we are
you you are
2 2
3 they 3 they are
(or Plural Noun) (or Plural Noun)
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