So you think you already know the difference between “must” and “have to”. Let's see if it's true.
1) First of all, watch this video about the forms and uses of both verbs. Did you know that “must” has not a past tense? How then can we express obligation and prohibition in the past?
2) As you probably know, modals can be also used to show different degrees of certainty in the past. Take a look at these examples and pay attention to the way in which “must have” is used.
3) Although both “must” and “have to” can be used in the present tense to express obligation with little difference in meaning, note the difference between the two past forms “must have + past participle” and “had to”:
a) He must have been ill (deduction)
b) I had to tell her the truth (obligation imposed by the speaker)
4) Now, let’s do some practice with these exercises:
5) Now it's your duty to practice with your language exchange. Use the modal verbs you have just learned. Remember: Make sentences and repeat them aloud.
6) Now let's learn some vocabulary with The Economist. Choose 10 words you don't know from this text, find their meaning, and make 3 sentences with each, and then check on the internet if there are similar sentences on native speakers' sites.
7) Listen and read this story. You should learn all the vocabulary and practice pronunciation.
8) Finally, write a short paragraph (about 120 words) using “must” (to express obligation, prohibition and certainty in the past) and “have (had) to” (to express both obligation and absence of necessity). Remember: Check your sentences by comparing them to native speakers' sentences on the internet.
If you have done all the exercises, then you've scored a 10! Congratulations! Imprimir