【课文讲解】

①spend some time doing sth

lifetime : 毕生精力

A. it costs sb some money to do sth

B. it takes sb some time to do sth

C. sb spend some money on sth

   sb spend some money in doing sth

D. sb pay for sth

②用不定式做目的状语: to abserve a new... 仔细观察,一般科学家用 “observe”

   which 引导定于从句

③notice that + 宾语从句

notice sth

notice sb do/doing : 注意到某人做某事/正在做某事

notice that: 文中可改为—He notice a river of liquid rock coming towards him.

river of...:...形成的河流 / river of soil and stone 泥石流 / river of blood 血流成河

④it threaten to: 有迹象表明

⑤so that : 以便于(目的状语从句),一定含有情态动词

  so…that

  such…that

  too…to

⑥take a risk of/at a risk of : 冒险

risk sth＝risk losing sth : 冒着失去......的危险

risk doing : 冒着做......的危险

⑦tell the time 报时(固定结构)

tell the difference between: 区分, 区别

tell (sb) a lie (谎言有很多个)

tell (sb) the truth (真话只有一个,故要特指, 加the)

tell (sb) the difference between

say a good word for sb : 为某人说好话

only just(固定短语)＝almost not : 差点就没有

on the subject of＝about