Student or Learner
what is the differnce between
have to and must ??
You must not cross the road when the traffic lights are red.
have to = external obligation
I have to do my homework.[my teacher asked me to do my homework]
"....it's also worth noting how to manipulate these expressions. For example "I don't have to do it." and "I mustn't do it." mean different things.
You go to a restaurant and the bill is $50. You are obliged to pay the bill but whether you leave a tip or not is your choice. You have to pay the bill but you don't have to tip. You must not leave less than $50 but you don't have to leave more than $50. " [source:]Page not found | Antimoon.com
IMPORTANT: The past form of 'have to' and 'must' is 'had to'. Must does not exist in the past or in the future.
e.g. I had to do my homework last night.
I`ll have to do my homework tomorrow morning.
NOTE: 'have to' is conjugated as a regular verb and therefore requires an auxillary verb in the question form or negative.
e.g. Do You have to do your homework?
Does she have to go to the market?
MUST : obligation is imposed by the speaker. The speaker has authority over the one that is spoken to and he/she exercises his/her power.
Must is also preferred to refer to ourselves (I must go now) and to express a strong advice or invitation (That's a picture you really must see).
You have to pass your exams if you want to succeed.
In England you have to drive on the left.
HAVE TO: obligation springs from circumstances or external rules. Something has to be done, whether the speaker likes it or not.
source:Obligation: must, have to, should