A:神经调节
B:激素调节
C:酶的调节
D:基因调节
使吸入的气体变得清洁的结构有( )
①声带 ②气管、支气管内表面的纤毛 ③ 鼻黏膜 ④会厌软骨 ⑤鼻毛
—Do you have enough nurses to take care of the injured?
—No, I think we need _______ nurses.
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