“西气东输”工程的起止点为 [ ]
A、西安—北京
B、三峡—上海
C、新疆—上海
D、拉萨—昆明
答案：C
one children want to challenge themselves by learning a language different from ______ their parents speak at home.
A．what
B．that
C．which
D．one
三极管基极的作用是什么？
