English grammar

Present Perfect

* The present perfect is formed by combining the auxiliary verb "has" or "have" with the past participle.

* We use the Present Perfect to say that an action happened at anunspecified time before now.

* We use the present perfect when we talk about the present result or effects of a past action.

Structure
Affirmative:
Pronoun + Have / has +verb Past participle..

Example:
* I have cleaned my room.

Negative:
Pronoun + Have not (Haven´t) / has not (Hasn´t) + verb Past participle

Example:
* I Haven´t cleaned my room.Question:
Have + Pronoun + verb past participle

Example:
* Have you cleaned your room?


Present Perfect Continuous

* We use the Present Perfect Continuous to showthat something started in the past and has continued up until now.

* We use this tense to show that something started in the past and has continued up to the present: an action or situation thathas just stopped or has recently stopped.


Structure
Affirmative:
Have/has + been + gerund…
Example:
* They have been traveling for two weeks.

Negative:
Have not (Haven´t) / has not(hasn´t) +been + gerund…
Example:
* They haven´t been traveling for two weeks.

Question:
Question + Have /has + been + gerund…
Example:
* How long have they been traveling?Past Perfect

The Past Perfect expresses the idea that something occurred before another action in the past. It can also show that something happened before a specific time in the pastThe past perfect is formed by combining the auxiliary verb "had" with the past participle.

Structure:
Affirmative:
Pronoun + had + Verb Past participle…

Example:
* You had studied Englishbefore you moved to New York.

Negative:
Pronoun + had not + Verb Past participle …

Example:
* You had not studied English before you moved to New York

Question:

Pronoun+ had (had...