In order to keep the balance of ecosystem, every possible means _______to deal with the problems of the over-exploiting of natural resources.
#101293
A
has tried
B
has been tried
C
have taken
D
have been taken
推荐题目
Linda make sure the table________before the guests arrive
#103768
A
be set
B
set
C
are set
D
are setting
I didn’t like Aunt Lucy, who＿＿without warning and bringing us presents.
#104416
A
always turned up
B
has always turned up
C
was always turning up
D
was always turned up
I'm tired out.I ________ all afternoon and I don't seem to have finished anything.
#99060
A
shopped
B
have shopped
C
had shopped
D
have been shopping
---I thought Tony should have won the contest. ---What a shame! He ________ just too nervous while playing.
#100533
A
had been
B
has been
C
was
D
would have been