()正弦电路中,瞬时值要小写:u、i。
A. 对
B. 错
Tom exchanged his penJohn’s toy.
A. to
B. for
C. in
He wants to play table tennis but can’t find a _________ (搭档).
A. classmate
B. partner
C. person
Driving on the mountain road makes him___________(紧张的\害怕的).
A. nervous
B. worried
C. upset