治疗咽喉肿痛首选穴是（）。
A、少冲
B、中冲
C、少商
D、商阳
E、涌泉
参考答案：C
—Is Betty _____ music now?
—Yes, _____. [ ]
A. listen to; she is
B. listening to; she is
C. listening to; she isn't
D. listen; she isn't
TCS不锈钢气体保护自动焊及半自动焊焊接工艺参数时，混合气体气瓶压力小于（）时停止使用。
A.3MPa
B.2MPa
C.1MPa
