The mother was trembling with anger . She ______her son and said nothing.

The director couldn’t figure out _______ made his assistant spend so much time in doing the survey. [ ]

iend Jane, even though she was busy, to your help when you were in trouble.——You are right, but it is like her to be selfish.

The number of students in our school ________ 2000 and a number of them ________ good at playing basketball.

下列语句中，语意明确、没有语病的一句是：（    ）