Ⅰ.单句语法填空
1．The famous player tried again and again after each failure. That is ________ he succeeded at last.
why [句意：每次失败后，这位著名的球员一次又一次地尝试。那就是为什么他最终成功了(的原因)。is后面是一个表语从句，用why引导从句，表示结果，故填why。]
2．The retired engineer is showing ________ the wheelchair climbs stairs, which all the curious visitors want to know.
how [句意：这位退休的工程师正在展示轮椅如何爬楼梯，这是所有有好奇心的游客想知道的。由句意可知，填how，意为“怎么，如何”。这是how引导的宾语从句。]
3．Dick enjoys painting but he knows the fact ________ he doesn't have what it takes to be a professional.
that [句意：迪克喜欢画画，但他知道自己没有成为一名专业画家所需要的(素质)。that引导同位语从句，说明fact的具体内容。]
4．Success partially depends on ________ you have the patience to do simple things perfectly.
whether [根据句子结构可知，设空处引导宾语从句；根据句意可判断，设空处意为“是否”，其前有介词on，故填 whether。]
5．I lost my cell phone yesterday. Can you tell me ______ I can buy one?
where [where引导宾语从句，且在从句中作地点状语。]
6．It never occurred to me ________ you could succeed in persuading him to change his mind.
that [it为形式主语，真正的主语为后面的从句，从句中不缺少成分，且句意完整，因此用that。]
7．________ is well known to everyone, I should say, is that a man becomes learned by asking questions.
What [分析句子成分可知，主语从句中缺少主语，且指事物，因此用what。]
8．Exactly ________ the potato was introduced into Europe is uncertain, but it was probably around 1565.
when [句意：土豆被引进到欧洲的确切时间不能确定，但很可能是1565年左右。分析句子结构可知，设空处为主语从句的引导词，根据around 1565判断，这里指时间，故填when。]
