1、The key to solve the problem is to find the car driver ( (解决问题的)线索;秘诀;答案 )
2、Through large amount of experiments, the scientists created a new rice ( 通过实施)
3、He told us the story of his escape from the enemy （逃跑;逃脱）
4、It is said that the hotel has been converted into a hospital （转换）
5、He may be too busy, that he forgot your birthday （很有可能）