Page 79 - Just Enough English Grammar Illustrated Book

You will see this pattern in the four examples of the verb watch:
Regular Verb Examples:

Today I watch the race.
Swim Meet I am watching the race.
at Lakewood
Pool Yesterday I watched the race.
I have watched the race every day.

This first group of verbs is called regular verbs. All regular verbs
display the same pattern of predictable changes.

The second group does not follow a regular pattern. Verb forms
in this group change for no apparent reason. There is no obvious
pattern you can apply when learning them.

Irregular Verb Examples:

We eat hamburgers.
We are eating hamburgers.
Yesterday we ate hamburgers.
We have eaten hamburgers
every day.

This second group includes verbs that are not regular. They are
called irregular verbs.

All verbs in the English language
can be divided into two groups:
regular verbs and irregular verbs.

Most English verbs are regular. Irregular verbs have verb forms
that require memorization before you can use them correctly.
There is no easy way to explain their changes and no way to
avoid memorizing their verb forms.

Let’s use what we have learned so far to build sentences.

4.5 The Four Principal Parts of a Verb
When you want to express an idea, you usually start with a
noun or pronoun that will become the subject of your sentence.
Once you know your subject, you need to state what the
subject does.
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