There is a widespread belief among the science world ____ we keep on _____  the earth as we are doing today, the existence of us humans on this planet will be out of the question in some years yet to come.

试卷相关题目

• 1— 'How long do you suppose it is _______ he left for Japan?' — 'No more than half a month.' 

  A.when

  B.before

  C.after

  D.since

  开始考试点击查看答案
• 2_____ I prefer a color TV, I have to buy a black and white one this time.

  A.As

  B.Since

  C.Because

  D.Although

  开始考试点击查看答案
• 3The American Civil War lasted four years ________ the North won in the end.

  A.after

  B.before

  C.when

  D.then

  开始考试点击查看答案
• 4____ most of the earth's surface is covered by water, fresh water is very rare and precious.

  A.As

  B.Once

  C.If

  D.Although

  开始考试点击查看答案
• 5Many people believe we will suffer from more environmental disasters _____we change the way we live.

  A.but

  B.although

  C.so

  D.unless

  开始考试点击查看答案
• 6I'm sorry you've been waiting so long, but it'll still be some time ______ Brian gets back.

  A.before

  B.since

  C.till

  D.after

  开始考试点击查看答案
• 7It helps ________ you pay attention to the social skills.

  A.when

  B.before

  C.the moment

  D.if

  开始考试点击查看答案
• 8Do you know how long it is ______we last went to the theatre?

  A.since

  B.before

  C.when

  D.that

  开始考试点击查看答案
• 9It will be worth trying _____it should not succeed at once .

  A.as if

  B.even though

  C.now that

  D.as long as

  开始考试点击查看答案
• 10______the Internet is of great help, I don't think it's a food idea to spend too much time on it.

  A.If

  B.While

  C.Because

  D.As

  开始考试点击查看答案