变压器外部故障有哪些？
参考答案：
绝缘套管严重破损、套管炸毁，造成单相接地或相间短路。
Yao Ming, who ______ the Houston Rockets, is working hard to make his dream come true.
A．joined
B．joined in
C．took part in
D．competed in
Betty asked me _______ to the museum with her. [ ]
A. go
B. goes
C. to go
D. going
