一.
1.去掉was
2.was后加an (experience 做“经验”讲时是不可数名词,做“经历”讲时,是可数名词.)
3.to 改为on
4.in 改为at,be good at 是固定短语,意为擅长于.
5.broke 改为 broken,broken在此处相当于形容词.
6.at 改为 on,on fire 意为 着火.
二.
1.We were caught in traffic jam on the way home yesterday.
2.They promised to help us with the work.
3.The little boy is saved by a soldier from the ruins.
4.It is reported that the concert will take place on Saturday next week.
5.London is the host city of next Olympic Games.(host作名词)
London will host the next Olympic Games.(host 作动词)