to 后面什么时候加 do 什么时候加doing to后面什么时候加do或加doing
to\u7684\u540e\u9762\u4ec0\u4e48\u65f6\u5019\u52a0doing\uff0c\u4ec0\u4e48\u65f6\u5019\u52a0to do\uff1f\u4e00\u822c\u60c5\u51b5\u4e0b\uff0cto \u540e\u9762\u5e94\u8be5\u63a5\u52a8\u8bcd\u539f\u5f62\uff0c\u5373\u4e0d\u5b9a\u5f0f to do.
\u4f46\u6709\u7684\u65f6\u5019\uff0cto \u4e0d\u662f\u4e0d\u5b9a\u5f0f\u7684to, \u800c\u662f\u4e00\u4e2a\u4ecb\u8bcd\uff0c\u8fd9\u65f6to\u540e\u9762\u5c31\u8981\u52a0\u540d\u8bcd\u6216\u52a8\u540d\u8bcddoing. \u5982\uff1a
I am looking forward to hearing from you soon. \u6211\u76fc\u7740\u4f60\u7684\u56de\u4fe1\u3002
Tom is not used to using chopsticks. \u6c64\u59c6\u4e0d\u4e60\u60ef\u4e8e\u4f7f\u7528\u7b77\u5b50\u3002
\u7a76\u7adfto \u662f\u4e0d\u662f\u4ecb\u8bcd\uff0c\u9700\u8981\u6211\u4eec\u5728\u5b66\u4e60\u8bcd\u7ec4\u65f6\u9010\u4e2a\u8bb0\u5fc6\u3002
\u4f60\u597d\uff0c\u5f88\u9ad8\u5174\u5728\u8fd9\u91cc\u56de\u7b54\u4f60\u7684\u95ee\u9898\uff1a
.
to\u505a\u526f\u8bcd\u65f6\uff0c\u540e\u8ddfdo
want to do
to\u505a\u4ecb\u8bcd\u65f6\uff0c\u540e doing
look forward to doing
say no to doing
pay attention to doing
prefer doing to doing
这两种情况一般上不能靠意义去区分，其实大多数情况下是加do的，加doing的词组只能见一个记一个了
to做不定式时加do
做介词时加DOING
一般都加do.
to后面加doing的情况除非短语要求to后跟名词性成分。
比如：look forward to hearing from you.
扩展阅读：teach to do ... 什么时候加to do全部 ... 什么时候用to do and do ... make 后面加do还是to do ... to do 开头是什么句型 ... 最高级后面加to do ... be used to doing ... 前do后do ... to a to b to c商业模式 ...
