问题
选择题
While ____ the dog, you should take care not to get loose . Otherwise, it may be dangerous to strangers.
A．walking;
B．walked
C．walking for
D．training for
答案
答案：A
考查状语从句的省略。“在遛狗时注意不要松手，否则狗会威胁到陌生人。”While （you are）walking the dog---
