课文详注 Further notes on the text
1．I thought so.我也这样想。
so 是代词，意为“这样”、“如此”。 I think so的否定式为I don't think so（我不这样认为）。类似用so的短句如：
I hope so.
I expect so.
I told you so.
2．have another look,再（仔细）看一眼。
3． look old,看上去老。
5．I'm sure she is.我肯定她有40岁了。
其后省略了 at least forty。
6．not more than twenty-nine myself,我自己还没29岁。
其中not more than是“不超过”、“不到”的意思。这里反身代词myself是I的同位语，用来加强语气。
She did it herself.
语法 Grammar in use
表示最有力的推论的最常用的形式是must和can't。这时，它们一般与系动词be连用。肯定的推断用 must be来表示，否定的推断用 can't be来表示，而不用mustn't。请看例句：
He can't be a doctor. He must be a dentist.
She can't be Danish. She must be Norwegian.
He can't be shaving. He must be having a bath.
It can't be cheap. It must be expensive.
He can't be ill. He must be tired.
词汇学习 Word study
She's a very famous actress.
To my surprise, he had a famous appetite.
This is famous weather for a stroll.
This antique vase is worth at least ￡20,000.
At least, you should consider our suggestions.
He has no plans to go abroad yet, at least as far as I know.
That party wasn't exciting at all, but at least it filled the time.
练习答案 Key to written exercises
1 He has to be here at six o'clock.
2 I think he is probably busy.
3 He has to be at the office early tomorrow.
4 I think he is probably sleeping.
5 I think he is probably French.
6 He has to be in France next week.
7 I think he is probably an engineer.