Modal verbs – Ability (CAN + COULD + BE ABLE TO)

Hello guys :) Today we start a new lesson, modal verbs! How useful are modal verbs concerning ability! For example, when you ask for something, for expressing that you are able to do certain things or when talking about possibility. For these situations, the English language uses the auxiliary verbs CAN and COULD.

Let's start with CAN: the verb "can", as we have said before, is an auxiliary verb and means ability in respect to something. The formula would be : Subject + auxiliary verb "can" + the verb that express the action you want to mention. For example:

I can play the piano

You can play the piano

He/She/it can play the piano

We can play the piano

You can play the piano

They can play the piano

- For the negation form you use cannot or the contracted form can't, for example "I can't sing very well". "We can't try again."

- For the interrogative form, as English auxiliary verb, the verb is now at the beginning of the sentence. For example: "Can you pass me the salt?"

CAUTION.

*The third person singular HAS NOT an "S" added to the verb. For instance: "She cans drink" would be totally wrong. "She can drink" is right. That is to say, this verb is invariable.

*When you formulate a sentence, the verb can is followed by an infinitive verb. Nevertheless, the tensemarker "to" does not fit. For example: "She can to drive" would be wrong. You must say "She can drive"

*When you formulate a sentence in nagation form, you can use the negation word, you can use it together or separated. "Cannot" or "Can not". Both ways are acceptable.

WHEN/IN WHICH TENSES do you use it?

We use it for present but it is also acceptable when speaking about future. For example: "I can do it tomorrow". So, as we can see, it is very flexible and quite easy to use. Nevertheless, when talking about past, we need to use a different way to express this ability. The key for doing this is "be able to". For this, you need to have to manage very clearly the verb to be. After this, everything is easy as a pie. Subject + be conjugated + able to + infinitive. For example -> "I was able to dance when I was a child."

Now let's talk about COULD. It is also an auxiliary verb. We use this one when making requests or talking in the past or ability.

CAUTION (the same problems with "can")

*Like the verb "can", "could" is never accompanied by the tensemarker "to"

*It is invariable. So, be CAREFUL! Here I let you an example:

I could talk

You could talk

He/She/It could talk

We could talk

You could talk

They could talk

- For the negative form, it is used "could not" or the constructed form "couldn't". For example: "I couldn't eat 10 hamburgers at once" or "I could not do that"

- For the interrogative form, it is an auxiliary verb too, so ,you should use it in the first position when asking something, for example: "Could you pass me the salt?"

WHEN do we use it?

- "Could" is used in contexts that are referring to the past, for example, "My grandmother could speak five languages".

- Or in specific situations, for example "They could not save her." or "I wish I could have fly"

IMPORTANT

When you ask for something in a very polite way (request to someone, asking for something to a person unknown, etc...) you use COULD. For example: "Excuse me, could you please tell me where is the closest supermarket?"

That's all. New exercises of this section are coming in order to clarify questions and doubts. And remember, feel confident to ask anything you want to say or add!

See you soon! :D