改句子 1.They have four singing classes every month.改为否定句

They have four singing classes every month.改为否定句

They don't  have four singing classes every month.

Tom has lunch in the school cafeteria.改为一般疑问句

Does Tom have lunch in the school cafeteria?

Jack keeps in touch with his parents (by e-mail).对括号里提问

By what does Jack keep in touch with his parents ?

It's time to go to school.保持原句意思

It's time for school.

.me,teaches,my ,maths,every evening,mother连成句子

My mother teaches me maths ,every evening.

it's time for after-school activities.保持原句意思 

It's time_to_  _do_ after-school activities.