Adverbs are expressions that function as modifiers of other elements in the clause. They can provide a wide range of information.

Time adverbs are often used with the present perfect and function as modifiers of other elements in the clause.

https://open.books4languages.com/english-a2-grammar/chapter/time-adverbs-with-present-perfect/

The Past participle is a verb that is used to form other tenses (such as the present perfect).

Many past participle forms of verbs are irregular.

https://open.books4languages.com/english-a2-grammar/chapter/past-participle/

The present perfect is a tense used to express  completed actions which have occurred in the past, are connected to the  present and still have effects on it.

When expressed in its interrogative form, the verb is used to ask questions.

https://open.books4languages.com/english-a2-grammar/chapter/present-perfect-interrogative/

The present perfect is a tense used to express  completed actions which have occurred in the past, are connected to the  present and still have effects on it.

When expressed in its negative form, the verb denies something about the subject.

https://open.books4languages.com/english-a2-grammar/chapter/present-perfect-negative/

The present perfect is a tense used to express  completed actions which have occurred in the past, are connected to the  present and still have effects on it.

When expressed in its affirmative form, the verb confirms something about the subject.

https://open.books4languages.com/english-a2-grammar/chapter/present-perfect-affirmative/

This book is the Grammar part of the A2 level of the practical guide  for learning English as a second language. It forms a part of book  series Books for languages. It is fully written in English and it serves  as a base for the adaptation to different mother tongues. Starting from  an integrated curriculum of languages, we offer an eclectic system with  a distribution of contents based on the need of learning objects.

English Grammar A1 Level: Conjunctions are words that function as a link between different clauses or elements in sentences.

https://open.books4languages.com/english-a1-grammar/chapter/conjunctions-and-but-because-when

English Grammar A1 Level: The imperative is a structure used to give an order or command.

https://open.books4languages.com/english-a1-grammar/chapter/imperative-mood

English Grammar A1 Level: Wh- questions always begin with one of the wh- question words (interrogative pronouns), which show what kind of information is wanted.

https://open.books4languages.com/english-a1-grammar/chapter/wh-questions

English Grammar A1 Level: Yes or no questions are also called closed questions or polar questions because the answer to them can only be yes or no.

The answers to closed questions are called short answers.

https://open.books4languages.com/english-a1-grammar/chapter/yes-or-no-questions