2019年mpacc考试英语真题——名词1122

{01}_____ of the students who took part in the military training is 450.

A.A number

B.A lot

C.Lots

D.The number

解析：考查数词。根据句中的谓语动词用单数，可知用the number of……的数目，其它选项谓语动词用复数。选D。
本题选D。
{02} American English has changed ________ time. There are several reasons ________ this.

A.over; for

B.for; with

C.in; of

D.during; about

解析：考查介词。change over time随时间改变；reason for……的原因。根据句意选择A。
本题选A。