Usamos must para indicar deber u obligación de hacer algo; podríamos traducirlo como tener que o deber. Cuidado, porque en su forma negativa, mustn't indica prohibición.  Should se utiliza para recomendar hacer algo y para afirmar si nos parece que algo es como debería ser o no.

Completa las siguientes oraciones con el verbo entre paréntesis y los modales 'should' o 'must' en afirmativo o negativo, según corresponda.

 

1 She (go) to university if she wants to be a doctor.

She must go to university if she wants to be a doctor.

 

2 We (take) an umbrella. It's going to rain.

We should take an umbrella. It's going to rain.

 

3 The exam is going to start. You (be) quiet.

The exam is going to start. You must be quiet.

 

4 You (read) the instructions before using it.

You must read the instructions before using it.

 

5 It's too hot. You (wear) a T-shirt.

It's too hot. You should wear a T-shirt.

 

6 He's drunk. He (drink) anymore.

He's drunk. He shouldn't (should not) drink anymore.

 

7 Tommy (finish) his homework before playing the guitar.

Tommy must finish his homework before playing the guitar.

 

9 You (not watch) TV so close. It can hurt your eyes.

You shouldn't/should not watch TV so close. It can hurt your eyes.

 

10 We (get up) early tomorrow to catch the flight.

We should get up early tomorrow to catch the flight.

 

11 (We/ wear) a helmet in the construction site?

Should we wear a helmet in the construction site?

 

12 James (hire) an exterminator, the house if full of bugs.

James must hire an exterminator, the house if full of bugs.

 

13 You (not eat) so many candies. It is bad for your teeth.

You shouldn't/should so many candies. It is bad for your teeth.

 

14 She (leave) the house. Her landlord sold it.

She must leave the house. Her landlord sold it.

 

15 The lesson is going to start in 10 minutes. You (be)

The lesson is going to start in 10 minutes. You must hurry up.