新斯的明属
A.M受体激动药B.M受体阻断药C.抗胆碱酯酶药D.β受体阻断药E.胆碱酯酶复活药
参考答案:C
It rains very heavily in this area, which has _____ annual rainfall of 7,000 mm, _____ ideal environment for
forests. [ ]
A. the; an
B. an; 不填
C. an; an
D. 不填; the
系统发育