Question

【题目】Seeing their teacher __________ into the classroom, they stopped __________ at once.
A.walk; telling
B.entering; to speak
C.enter; to tell
D.walking; talking

Answer 1

【答案】D
【解析】walk into=enter 故排除B，C。A选项中的tell是及物动词，故排除A。see sb doing sth 看见某人正在做某事 stop doing sth 停止正在做的事。句意：看到他们的老师走进教室，他们立刻停止了说话。故选D。