喉上部血液供应的动脉主要是（）。
A.甲状腺上动脉
B.甲状腺下动脉
C.舌动脉
D.喉下动脉
E.以上都是
参考答案：A
We could see nothing because the lights suddenly . [ ]
A. went on
B. went over
C. went down
D. went out
活塞在进气冲程上止点前42020’曲轴转角时，该缸进气凸轮使（）的升程按技术要求为0.38mm，这一数值叫做0.38尺寸。
