reads a book

is reading

is reading a book

was reading a book

They have finished their homework.

They will finish their homework.

They are finishing their homework.

They finished their homework.

have/has + being + verb

have/has + been + verb+ing

have/has + verb + ed

have/has + been + verb

I read a book yesterday.

What do you do?

I will read a book later.

Friend 1: What are you doing? Friend 2: I am reading a book.

is

am

was

are

The verb should be 'goes'.

The sentence is correct as is.

The subject should be 'They'.

The verb should be 'going'.

have/has + past participle

had + past participle

will + base form

am/is + present participle

The first states a current fact; the second emphasizes duration.

Both sentences mean the same thing.

The first emphasizes duration; the second states a current fact.

The first is a question; the second is a statement.

I am studying for three hours.

I will study for three hours.

I have been studying for three hours.

I studied for three hours.

To indicate past events

To describe actions happening right now

To express future plans

The simple present tense is used for habitual actions, general truths, and facts.

are playing

playing soccer are

They are soccer

are playing soccer

Adding 'ed' for all verbs in the simple present tense.

Using 'do' or 'does' with all subjects in affirmative sentences.

Using the simple present tense for past actions.

Forgetting to add 's' or 'es' for third-person singular subjects.

Use the auxiliary verb 'do' before the main verb.

Use the past tense of the verb with the subject.

Use the base form of the verb with the subject.

Add 'ing' to the verb for present continuous.

I ate

I am eating

I have eat

I have eaten.