Question

The naughty boy had wanted to play football with the kids in the street, but his parents warned him ____.

A．not to

B．not to do

C．to do

D．of doing

Answer 1

A

试题分析：考查不定式的省略：句意：调皮的男孩想和街上的孩子踢足球，但是他的父母警告他不要（踢球）。这是省略句，完整的是his parents warned him not to play football。不定式的动作如果前面出现了，可以省略动词do，但是to要保留。选A。
点评：为避免重复，有时可用不定式符号to来代替整个动词不定式(短语)。但是如果动词是be动词或have，就不能省略。