`1.` How many teachers are there in your school?
`2.` Does your sister go to school on foot everyday?
`3.` I spend two hours doing my homework every night.
`->` It takes sb time to do sth : ai đó mất bao lâu để làm gì
= Sb spend time doing sth : ai đó dành bao lâu để làm gì
`4.` Tung is the most intelligent in our class.
`5.` How heavy is your son ?
`6.` Why don't we sing and dance.
`->` How about = what about + Ving
= why don't we/you + Vinf
`7.` I'm the strongest in my school.
