填空题

As research techniques become more advanced, the number of animals ______ (use) in experiments may decrease.

【参考答案】

used

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填空题

In 1991, after the Gulf war, Bush’s ______ (approve) rating reached 91 percent, the highest level recorded since polling began in the 1930s.

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What did they do in the partyThey ate, ______, and ______.