① Emma watches television for about twenty hours a week.

② Emma watches television for about twenty hours a week.

请问对这两句的提问到底是 How long a week...? 还是 How many hours a week...?

【答】第2句的划线不正确。for 跟hours 有关，about twenty 是定语，应在about twenty 下面划线。改为： 

② Emma watches television for about twenty hours a week.

那么，这两句的提问分别是：

① How long does Emma watch television a week?

② For how many hours does Emma watch television a week?