Visiting relatives can be awful.
两种意思：1、到访的亲戚可能会令人不快.2、拜访亲戚可能会令人不快.
改为：1、Relatives who are paying a visit can be awful.
2、It can be awful visiting relatives.

These are synthetic buffalo hides.
两种意思：1、这些是人造的水牛皮.2、这些是人造水牛的皮.
改为：1、These are buffalo hides that are synthetic.
2、These are hides of synthetic buffalo.

John loves Jane more than Tony.
两种意思：1、John爱Jane胜过爱Tony. 2、John爱Jane胜过Tony爱Jane.
改为：1、John loves Jane more than Tony does.
2、John loves Jane more than he loves Tony.