【单选题】"He never told the people whom he worked with what she gave him, because it was a secret." What is "he never told the people whom he worked with what she gave him"?
【简答题】阅读短文,根据所读内容, 在下表中的空格处填上适当的单词或短语, 每空不超过3个单词。 Cloning has caused much debate..On the one hand , some scientists think valuable tissues and organs can be used to save human lives .On the other hand , som...
【单选题】_______cloning human embryos is not legal in many countries, some scientists are already pushing ahead with research in order to produce a cloned human baby.