The professor thought that I was making good progress in my studies and told me to __________.

A. keep up

B. go ahead with

C. hold back

D. come up with
出自:中北大学-大学英语(二)

完成拼图验证

按住下方滑块,将拼图拖到缺口处后松开。

拼图背景,将小拼图拖到缺口处
向右拖动滑块