UNIT 5 5

Modal Verbs: Should, Must, Have to

Leia o texto a seguir e observe o uso do verbo modal should

How Can I Prevent Noise-Induced Hearing Loss?

earbuds: fones de ouvido

The best way to prevent noise-induced hearing loss is to protect your ears from loud noises:

• Move away from loud sounds or speakers.

• Turn down the volume when listening to music or watching TV. When wearing earphones or earbuds, you should be able to hear conversations around you.

• Take breaks after listening to music with headphones or earbuds for more than 1 hour at a time. (…)

No texto, o verbo modal should é utilizado para oferecer uma recomendação de como prevenir perda de audição ao utilizar fones de ouvido (“When wearing earphones or earbuds, you should be able to hear conversations around you”).

• Usamos, geralmente, o verbo modal should para indicar aconselhamento, recomendação, e o verbo modal must ou have to para indicar obrigatoriedade, necessidade. Note que usamos verbos modais antes de um verbo principal no infinitivo (sem a partícula to).

You should do more exercise. It would do you good.

All students at this school must wear a uniform. You have to drive carefully. If not, you may get involved in a car accident.

• Para formar frases negativas com should, usamos not depois do verbo modal e antes do verbo principal.

You should not let others dictate what is good for you. Parents shouldn’t choose their child’s career.

• Para formar frases negativas com have to, usamos um verbo auxiliar na negativa (don’t/doesn’t/ didn’t/won’t) antes de have to

You don’t have to follow in your parents’ footsteps if it’s not what you want. You won’t have to cry anymore. It’s over.

• A forma must not indica proibição. Para indicar ausência de necessidade ou de obrigação, usamos a forma negativa de have to

You must not come to the party because you were not invited. You don’t have to come if you don’t want to.

• O verbo modal must não tem uma forma para expressar o passado e, quando desejamos expressar a mesma ideia no passado, usamos a forma had to

Yesterday I didn’t have to stay up late studying. When I was younger, I had to walk to school every single day.

Extra Practice a. “The best are noise-canceling headphones, which help block out other noises. That way, you (should/don’t have to) turn up the volume on your music as loud to hear it well.” don’t have to b. “Prescription ear drops usually cure swimmer’s ear in 7–10 days. The pain (should/don’t have to) ease within a few days of starting treatment.” should don’t have to

Replace each icon with the correct form of the modal verbs in parentheses to complete the following sentences.

Modal Verbs: Should, Must, Have to Habilidades da BNCC

O exercício do boxe Extra Practice contempla a seguinte habilidade da BNCC: