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 /accomplishing/to accomplish）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。 Why is case study investigation essential for all Management students before their case study assignment report? Most of us are common with 4 kinds of case studies ... https://riverazjjr.bloguetechno.com/5-simple-techniques-for-case-study-solution-72243594