__________ migrate long distances is well documented.




A.That it is birds
B.That birds
C.Birds that
D.It is that birds

________(4)




A.who
B.whom
C.whose
D.which

_______(9)




A.successfully
B.successful
C.success
D.susceed

I don't have a computer.




A.I wish I have a computer.
B.I wish I had a computer.
C.I wish I had had a computer.
D.I wish I would have had a computer.

He is good at studying Chinese, ________________?




A.is he
B.isn't he
C.was he
D.wasn't he

It was not until the end of prehistoric times that the first wheeled vehicles appearing.




A.not until the end
B.prehistoric
C.the first
D.appearing

A.reign
B.reindeer
C.protein
D.vein

A.exact
B.examine
C.eleven
D.elephant

The word “handheld” in the passage is closest in meaning to______




A.handling manually
B.held by hand
C.controlling hands
D.operated by hand

A chronic lack of sleep may make us irritable and reduces our motivation to work.




A.uncomfortable
B.responsive
C.calm
D.miserable