Without these achievements, the opening of the west ____
A. couldn't occur
B. needn't have occurred
C. couldn't have occurred
D. can't occur
查看答案
You don't need to consult with anybody else. Actually the best person ____ is your mother.
A. to talk to
B. to talk
C. talking about
D. whom you talk
____ any area receives more water than the ground can absorb, the excess water flows to the lowest level, carrying loose material.
A. Being
B. Whenever
C. When might
D. Is
____ people depend to such a great extent on forests, every effort must be made to preserve trees and wildlife.
A. For
B. Since
C. Before
D. Because
She, we believe, burnt her midnight oil for the whole week, ____ she got very good marks for all her subjects.
A. for
B. because
C. since
D. as