Quick Test #07 Pre-intermediate Infinitive and Gerund, have to, don't have to, must, mustn't

We use have to to talk about things that are necessary because of rules that other people oblige us to follow: M y brother has to travel a lot in his job. (It is required by his employer.) We have to pay the rent every month. (It is required by the landlord.) We use m u s t when the speaker thinks it is necessary or im portant to do an action: You must go. (= It is important that you go.) We make negatives, questions and short answers like this: You m ustn’t go. M ust you go? ~ Yes, I must.