【问】 That sentence was so hard to understand that I had to have my teacher to explain it forme.(全国高考英语试题，1980)

请分析这个句子的错误。

【答】 标准答案规定将to explain改为explain。但实际上，explein it for me的说法是罕见的。大家知道，某些动词要求用介词来引出间接宾语，但是，哪个动词要求哪个介词，是约定俗成的。有的要求介词to，有的则要求介词for或of等等。而explain通常要求用介词to。请对比下列实例：

1. She made a meal for Pual.(CGEL)

她为保罗做饭。

2. She asked a favour of Pual.(对比：She asked Pual a favour.)(CEGL)

她请保罗帮个忙。

3. He bought a present for Jane.(LEG)

他给简买了一件礼物。

4. Say it to me.

把那件事告诉我吧。

5. Please explain this rule to me.(Palmer)

请把这个规则给我讲一下。

6. The speaker tried to explain his meaning to the crowd.(LDPV)

讲演者试图把他的意思向群众讲清楚。

请做下面的英语试题：

As you probably know，our host____，Duncairn is one of a small group of castles built inthe twelfth century on the western coast of Scotland.

A. was explaining to us B.was explaining us

C. was remarking us D. was telling to us(Nelson，400D)

(参见 have sb.do/to do)