掘进工作面采用锚杆支护时,锚杆外露长度在()cm为合格。
参考答案:3-5
John is hungry. He _____________ some potatoes.[ ]
A. would like to
B. have
C. would like
喷嚏反射的生理意义在于()
A.因鼻腔局部刺激和病变引起支气管病变
B.清除鼻腔中的异物和刺激物
C.提示有变应性鼻炎
D.减少鼻腔腺体的分泌
E.增进食欲