He's studying a maths test. [ ]
A. at
B. for
C. to
D. with
答案：B
My brother is having fun ______ model planes. He has made many model planes. [ ]
A. make
B. making
C. makes
D. to make
我国正在实施“宽带中国”战略，主要是提升用户接入（）的带宽，提升信息应用水平。
A.固定电话网
B.国际通信网
C.互联网
D.全球卫星网
