1.Her mind has been too______with passing the exam to think about a holiday.答案是填occupied,为什么不填filled,不是be filled with吗?

1.Her mind has been too______with passing the exam to think about a holiday.答案是填occupied,为什么不填filled,不是be filled with吗?
2.don't you think it is the shop's owner,rather than the sales girls,____to blame?
答案是填that is,为什么不直接用is?
3.Nole likes playing football,but he doesn't like playing basketball,____
答案是填it is the same with jack.为什么不是 so dose jack.反正都是实意动词like打头嘛.
4.so much time___,the research was only half done.
为什么要用having been spent ,有先后顺序?