18 和 24 的最大公因数是，3 和 5 的最小公倍数是.

The children have some apples.(改为单数句子)

We can see some birds over there.(对画线部分提问)

Look out of the window.(改为否定句)

The boys are sitting under the tree.(对划线部分提问 )

We are making a model plane.(变成一般疑问句 )

Jason is used to(watch) TV the whole night.

Look at the sign. The library is(close) from 1:00 p.m to 2:00 p.m.

I think the(four) lesson is the most difficult in this book.

Janet(get) up at 7:30 a.m. every day, so she is always late for school.