該用to do sth還是to doing sth?

請看下面一題：

The chemistry teacher required the students _________ more attention _________ the lab clean.

A. to pay, to keep                            B. to paying, to keeping

C. to pay, to keeping                        D. paying, keeping

【分析】此題容易誤選A，認為空白處應填兩個不定式。其實正確答案是C，第一空填不定式，即套用 require sb to do sth (要求某人做某事)句型，而第二空則應填 to keeping，因為 pay attention to(注意)中的to 是介詞，不是不定式符號，所以其后接動詞時要用動名詞。類似地，以下各結構中的 to 也是介詞，不是不定式符號，后接動詞時應用動名詞，而不是動詞原形：

devote one’s time to doing sth 把某人的時間用于(奉獻于)做某事

be [get] used to doing sth習慣于做某事

be equal to doing sth 等于做某事，能勝任做某事

What do you say to doing sth 你認為做某事怎么樣

be accustomed to doing sth 習慣于做某事

look forward to doing sth 盼望做某事

be opposed to doing sth 反對做某事

object to doing sth反對做某事

stick to doing sth 堅持做某事

get down to doing sth 開始做某事

take to doing sth 喜歡上做某事

admit to doing 承認做了某事

pay attention to doing sth 注意做某事