До ть будласка дуже треба 2 варіант. 1.Our teacher explained the English grammar. 2.He visited his parents last week. 3.The waiter brings me the dish. 4.The manager didn't phone the secretary this morning. 5.They keep the room tidy all the time. 6.Millions of people read different newspapers.​

Глагол to be может быть глаголом-связкой в именном сказуемом (в значении "есть").Формы глагола to beI am-я есть (существую) He / She / It is-он, она, оно есть (существует) We are-мы есть (существуем) You are-ты, вы есть (существуете) Тhey are-они есть (существуют)
глагол to be может быть глаголом-связкой в именном сказуемом (в значении "есть").-I am a doctor.Я врач. (Я есть врач.)
Чтобы задать вопрос нужно поставить глагол to be перед подлежащим:Am I happy?
Для образования отрицательной формы достаточно поставить отрицательную частицу not после глагола to be:I am not happy.

They say Mr.Voronin (works/work/working/does working) in the office. Do you seldom stay (in/at/on/ничего) home? Our engineers often (starts/start/starting/starten) work at 9 o'clock. He lives in Berlin, (isn’t/doesn’t/livesn’t/does) he? She (meets/is meeting/meet/meeting) foreing businessmen every day. (have/has/is/are) there any contracts with GML company? Mary asks if we (would going/goes/will go/do go) to the country.  Usually they meet (from/after/in/from) lunch. He was charged with a serious (outrage/insult/annoyance/offence). She is (after/on/at/for) business. Mr.Brown came out of the office at 2 p.m.The car (was waiting/wait/waiting/is waiting) for him. She (am/be/are/is) a manager. He usually has lunch (for/at/in/on) 2 o’clock. It (am/to/is/are) a file. Where (where/is/was/are) you the day before yesterday? were (Hertz/volt/walt/ampere) is the new unit of frequency adopted in 1960. Where is Jane?I am (tired with/tired about/tired of/tired to) waiting? They wonder how many customers we (has/have/having/do have). Britith Businessmen are interested (at/to/in/for) buying new models of planes. He … never … this name.(have heard/has heard/have hear/heard). Who (does speak/speak/do speak/speaks) three foreign languages in you group? There (amn’t/aren’t/isn’t/haven’t) his letters. We (have studied/has study/studying/studies) the contract from in detail.