在低压工作中，人体及所携的工具与带电体的距离应大于20厘米。
参考答案：错
I_______ on the summer holiday. [ ]
A. have a great time
B. has a good time
C. had a good time
D. had great time
论述饭店连锁集团的优势表现在哪些方面？
