there be句型中用动词不定式做后置定语或者动词ing的如何做?
我说几个句子：
1.There will be a lot of things ____.A.to see B.seeing
动词不定式做主语,为什么不能选B?还是说是按语意来的?= =
2.There are a lot of people ____.A.to run B.running
外加一个例句：
Many people in the world live in big citis,which are ofen dirty and
difficult places ____.A.to live B.living
why?