题目

_______ is troubling me is ______ I don’t understand ________ he saidA.What; that; what B.What; what; whatC.That; that; what D.Why; that; which 答案：【答案】A【解析】考查名词性从句。句意：我烦恼的是我不明白他说的话。第一空是主语从句，从句中缺主语，要用What；第二空是表语从句，从句不缺成分，所以要填that；第三空是宾语从句，从句中的动词understand缺宾语，要填what。综合分析可知选A。如图，已知AB=AD，∠BAE=∠DAC，要使△ABC≌△ADE，若以“SAS”为依据，补充的条件是 ．