展开全部 在but后何时要接带to的不定式，何时要接不带to的不定式有一条简单的规则。那就是前面动词是do（does/did/finished /carrying out/to do）时，后接不带to的原形不定式；如前面用的是其他的动词，则后面的不定式要加上to。 Case study is practically nothing but an in depth research that relies on the scientific methodology. The leading goal in the case study essay assignment is to describe true... https://casestudyhelp41481.blogocial.com/top-latest-five-case-study-analysis-urban-news-72715386