In English we use should / shouldn't /ought to / oughtn't to give advice. We use should / ought to to say something is a good thing to do and shouldn't / oughtn't to say something is a bad thing to do.
Example sentences :
Note : To ask for advice we can say: What should I do?
In English, "can" is a modal verb and only has a present, past and conditional form. It can also be used with a future meaning.
Example sentences :
Note : Can is not used to talk about specific possibilities.
Example sentences :
In English, could is used to talk about past ability/ permission/ possibility.
Example sentences :
"Be able to" can be used in the present, past, future, present perfect and as a gerund or infinitive.
Example sentences :
Note : be able to in the present and past is more formal than can or could.
In English we use might or may to say something in the future is possible, but not decided.
Example sentences :
To make questions with might we usually use Do you think...?
Example questions :
In English we can also use might in short answers.
Example short answers :
In English we use have to + infinitive to say something is necessary or obligatory. We normally use have to for a general obligation from an outside source, such as work or the law.
Examples sentences :
In English we use don't have to + infinitive to say something is not necessary or obligatory. It means you can if you want to, but it's not necessary.
Example sentences :
To make questions we use do/does.
Example questions :
Form : ( Must + infinitive without to )
In English we use must + infinitive to talk about rules and obligations. We normally use must when the speaker imposes the obligation, such as a teacher to students, or even to yourself.
Form : ( Mustn't + infinitive without to )
In English we use mustn't + infinitive to say something is prohibited.
Example sentences :
Note : You can often use can't or be + not allowed to instead of mustn't.
Example sentences :
Note : Mustn't and don't have to have completely different meanings.
Mustn't Vs Don't Have To
Note : Have to is a normal verb and exists in all tenses whereas must is a modal verb and its only forms are must and mustn't.
You can also use have to and must for strong recommendations.
Example sentences :
In English we use must when we are sure something is true.
Example sentences :
In English we use may or might when we think something is possibly true.
Examples sentences :
In English we use can't when we are sure something is impossible.
Examples sentences :
Note : In this context, the opposite of must is can't, NOT mustn't!
In the past, can't, could, may, might and must for probability change to can't have, could have, may have, might have and must have + past participle (Verb 3).
In the past, should and ought to change to should have and ought to have + past participle (Verb 3).
Note : the form of "must" for obligation and "can" are exceptions.
Must for obligation changes to had to + infinitive
Can changes to could or was able to
Modal example sentences | |
---|---|
But he can't walk on it. | Mas ele não consegue andar sobre ela. |
No way, what else can I have instead of chips? | Não pode, o que eu posso pedir em vez de batatas fritas? |
You must work very hard. | Você deve trabalhar muito. |
Hello guys, I can hear you shouting from upstairs. | Oi caras, eu consigo ouvir vocês gritando lá em cima. |
Since I can't smoke in the room, I have to go to the garden. | Já que não posso fumar no quarto, tenho de ir para o jardim. |
Umm, can I do it after I smoke? | Hum, posso fazer isso depois de fumar? |
As you might know, you should always keep an eye on your stuff at pubs. | Como você deve saber, você deve sempre ficar a tento a suas coisas em pubs. |
Same, I can take you out for dinner! | O mesmo, eu a levo a jantar fora! |
Hm... All the stuff on the left hand side can go. | Hum... Todas as coisas que estão no lado esquerdo podem ir. |
But I have to do it sometimes to visit my family. | Mas tenho de as fazer de vez em quando, para visitar minha família. |
Impossible dear, you can smoke in the kitchen or the garden! | Impossível, querido, você pode fumar na cozinha ou no jardim! |
So I guess we have to see the next one now. | Portanto, julgo que agora vamos ter de ver a próxima casa. |
I'm sorry, I can't go any lower than 175! | Lamento, não posso descer abaixo dos 175! |
Can't you have the meeting another time? | Não pode marcar a reunião para outra altura? |
The burglar might like it. | O ladrão pode gostar delas. |
Hm, I would like to see her, but I don't think we should disturb her. | Hum, eu gostaria de a ver, mas eu não quero incomodar. |
I don't want to upset you, but I have to tell you something! | Eu não quero aborrecer você, mas eu tenho de contar uma cosa para você! |
Or maybe I can have some drinks with friends from work. | Ou talvez vá tomar umas bebidas com os amigos do trabalho. |
We can get the other things on the way back. | Podemos pegar as outras coisas no regresso. |
You should, it might be more helpful to find some houses around here. | Devia fazê-lo, pode ser mais útil para encontrar casas por aqui. |