图形符号（）表示N型单结晶体管。
A、A
B、B
C、C
D、D
参考答案：C
After the Shenzhou-9 manned spacecraft was successfully launched, Liu Yang became the first woman astronaut ________space in China.
A．to enter
B．enter
C．entering
D．entered
通过正方形的学习，你有什么收获？
