I want everyone to sing ___________! [ ]
A. loudly
B. loud
C. cloud
答案：A
选择填空。
A: Nice to meet you.
B: . [ ]
A. Nice to meet you, too.
B. How are you?
C. Hello.
A．温度传感器
B．红外线传感器
C．生物传感器
D．压力传感器
