I'm glad you here. [ ]
A. to meet
B. meets
C. meeting
D. met
答案:A
简述运用6-DMAP诱导多倍体的原理?
挫折后捶胸顿足、嚎啕大哭,这种受挫后的外部行为反应是()
A.冷漠
B.攻击
C.倒退
D.固执