Поставьте следующие предложения в вопросительную и отрицательную форму. Their office hours begin at 9 o’clock. Mr.Bell

Their office hours don\'t begin at 9 o’clock.

Do their office hours begin at 9 o\'clock?

Do their office hours begin at 9 or at 10 o\'clock?

When do their office hours begin?

Whose office hours begin at 9 o\'clock?

What begins at 9 o\'clock?

Their office hours begin at 9 o\'clock, don\'t they?

Mr. Bell isn\'t busy all day.

Is Mr. Bell busy all day?

Is Mr. Bell or Mr. Brown busy all day?

How long is Mr. Bell busy?

Who is busy all day?

Mr. Bell is busy all day, isn\'t he?