In this English lesson you will learn how and when to use MUST or HAVE TO in English.
Difference number one
Look at these two sentences:
I must go and get my eyes tested. I don't see very well.
I have to get and get my eyes tested. The doctor told me so.
Basically, the difference is that in the first sentence, I think it is necessary to get my eyes tested.
In the second sentence someone else thinks that it is necessary. It is not my opinion. It is the opinion of another person, in this case a professional.
Difference number two
Take a look at these sentences:
You mustn't smoke on public transport.
You don't have to work today. It's Saturday.
In the first sentence it is necessary NOT to smoke on public transport because it could be against the law.
In the second sentence it is not necessary to work on Saturday because it is a holiday. You can work if you want but you don't have to.
Past and future use
When we take about the past, or the future with 'will', we use 'have to'.
I had to buy a new suit yesterday. My old one is too small.
I will have to buy a new suit soon as my old one is too small and doesn't fit me anymore.
He had to take the day off yesterday as he was sick with the flu.
Must for recommendations
We use must when we want to suggest or recommend something strongly.
You must have lunch at that new Japanese restaurant. The sushi is fantastic.
We must visit Barcelona again. We loved it the last time we were there.
Here's another English grammar lesson for you to look at.
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