Express the following sentences using MUST / MUSN'T / HAVE TO / DON'T HAVE TO

E.g.	It is an obligation not to drive on the left in Farnce.
	You on the left in France.
1	If you want to lose weight, my advice to you is to eat less fatty foods.
	I think you less fatty foods if you want to lose weight.
2	It isn't necessary to be very strong to be a fireman but it helps.
	You very strong to be a fireman.
3	We were obliged to take a detour as we were driving over to see them.
	We a detour as we were driving over to see them.
4	To be a good chef, it is necessary to love food.
	You food to a good chef.
5	When doing business in Germany, you are advised to be on time.
	When doing business in Germany, you on time.
6	It is a very good idea to back up your computer weekly.
	You your computer weekly.
7	It is an obligation not to break the law.
	You the law.
8	I have found that it is necessary to have a lot of patience in my work.
	I very patient in my work.
9	An engineer is obliged to be very precise in his work.
	An engineer very precise in his work.
10	It won't be necessary to arrive at the party before 8.30 next Saturday.
	We at the party until 8.30 next Saturday.