Tom was absent from school this morning,because sometimes he was a little weak and could ______ill .

（湖南省怀化市2014年高三第二次模拟考试）30. , and you will realize your dream of being successful.

He pretended to be a doctor, but _____ he is a cheat[ ]

I think it is ______ useful advice, so I will always remember it.

Hainan is a very good island. It’s the second ________island in China.