1.the bike cost at least 500 yuan.
It will cost you at least 500 yuan in bying th bike
翻译：这辆自行车至少要500元
2.it's nice of you to help me.
You are nice to help me
翻译：你能帮我真是太好了
3.city air is dirty,so it is wise of you to wash your hair often.
City air is dirty,you'd better wash your hair often
城市的空气很脏,你最好常洗头.
4.simon is not carefl enough to do the job.
It's it not careful enough for Simon to do the job
西蒙在做这个工作的时候不够细心.
5.i am less hard-working than our monitor.
I am not so hard-working as our monitor
我没有我们的班长那样勤奋.
6.Mary doesn't speak English as well as Jane
Mary doesn't speak Englsh better than Jane.
玛丽的英语没有简说的好.