要看to是什么词性 {【当to为介词时,to后面加动词ing形式】} 例如:hold on to doing sth.坚持做…… look forward to doing sth 盼望做某事 be opposed to doing sth 反对做某事 object to doing sth反对做某事 stick to doing sth 坚持做某事 be used to doing sth.习惯于做某事(used to后是to do sth. 意思是过去常常做某事,前面有没有be很重要)
等等 {【当to不为介词时,to后用动词原形】} 例如: want to do sth.想要做某事 be supposed to do sth. 应该做(被期望做)某事 (=should do sth) 【初中阶段只有几个词后面只能接动词ing,其余的都可接to do sth. 例如:practice doing sth 练习做某事 consider doing sth 考虑做某事 等等 有些词既可以接to sth又可以接doing sth like to do sth/like doing sth love to do sth/love doing sth hate to do sth/hate doing sth 等(有点说多了哈)】 总而言之,动词短语接to doing是一种to作为介词的用法。 Good luck
此处but为介词,意为"除...之外" 当but前面有动词do或do的其他变化形式时,只加动词原形.如:i did nothing but wait there for two hours. 而but前面无动词do或其变化形式时,则要加不定式.如:i couldn't say anything but to stand still silently.
第2个回答 2013-06-08
作为动词词组固定搭配里的to do sth是用原形的 但是作为介词后面的动词连接 是需要ing形式的