The imperative

English Grammar | The imperative |  Imperatives are used to issue commands. They use the infinitive of verbs (dropping the word
"to"); in the first person plural ("we"), the infinitive is preceded by "let's" (or: "let us"):
· Speak!
· Finish your homework!
· Let's eat!
· Close the door!
The negative imperative is formed by placing "don't" (or "do not") before the imperative form; in
the first person plural one uses "let's not" (or "let us not") :
· Let's not forget who helped us.
· Don't leave me!
· Don't walk on the grass!
· Please don't eat the daisies!
The imperative has no effect on the word order of the rest of the sentence.
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English Grammar : PRESENT PERFECT

English Grammar | English Grammar : PRESENT PERFECT | Main uses:
1. Past actions with results/consequences in the present.
Paul has eaten all the cookies.
When was the action done? In the past: a few minutes ago/yesterday.
Consequence? There is no cookie left. There is nothing left for me.
2) Actions which began in the past and are still in progress.

• Paul has lived in London for 10 years.
• When did it start? 10 years ago.
• Is it finished? No, it isn't. Paul is still in London. He lives in London.

SYNTAX: HAVE (or HAS with he/she/it) + PAST PARTICIPLE

• I have done my homework. She has done her homework (verb: do)

NEGATIVE:
I have not done my homework. = I haven't done my homework. She has not done her homework.
= She hasn't
done her homework.
QUESTION:
Have you done your homework? Yes, I have. / No, I haven't.

English Grammar : Present Perfect Tense

Learn Grammar | English Grammar : Present Perfect Tense | Study this sentences :

• Dorothy has killed the Wicked Witch of the East
• How many people has Dorothy met on her adventure?

In the sentences above, we use present perfect tense to express things we have done in our lives or our achievement. We do not usually give the exact time.

Here is the pattern: