This is a process happens when land becomes desert people cut down trees and dig up grass.
#33051
A
when; because
B
that; because of
C
when; because of
D
which; because
推荐题目
___ surprised me most was ____ he was too late for the important meeting, for he was chairman of it.
#32071
A
What; why
B
That; how
C
What; how
D
That; why
When the students heard the alarm, they all hurried to they thought was an emergency exit door．
#30175
A
what
B
which
C
where
D
who
The other day ,my father drove his car at _____I thought was a dangerous speed.
#32075
A
as
B
that
C
what
D
which
Scientists say it may be one year or so ________ it is possible to test the new medicine on human patients.
#32551
A
when
B
after
C
before
D
since