Can / Could

Can

Use can in a sentence

(noun)

1. The definition of a can is a container normally made of metal with a lid.

An example of can is what tuna comes in.

verb

1. Can means someone or something knows how to, is able to, is likely to or has the right to do something.
   1. An example of can is someone knowing how to play the piano.
   2. An example of can is a cat being able to paint.
   3. An example of can is a car that usually starts.
   4. An example of can is someone having the key to a neighbor’s house and being able to enter if they’d like.

Can (auxiliary verb)

1. know(s) how to
2. am, are, or is able to
3. am, are, or is likely or at all likely to: can that be true?
4. have or has the moral or legal right to
5. Informal am, are, or is permitted to; may

Can (aux.verb)

1. a. Used to indicate physical or mental ability: I can carry both suitcases. Can you remember the war?

1. Used to indicate possession of a specified power, right, or privilege: The president can veto congressional bills.
2. Used to indicate possession of a specified capability or skill: I can tune the harpsichord as well as play it.

1. a. Used to indicate possibility or probability: I wonder if my long lost neighbor can still be alive. Such things can and do happen.

1. Used to indicate that which is permitted, as by conscience or feelings: One can hardly blame you for being upset.
2. Used to indicate probability or possibility under the specified circumstances: They can hardly have intended to do that.

1. Usage Problem Used to request or grant permission: Can I be excused?

can

Verb

(third-person singular simple present can, present participle -, simple past could, past participle couth (obsolete except in adjective use))

1. (modal auxiliary verb, defective) To know how to; to be able to.

She can speak English, French, and German.   I can play football.   Can you remember your fifth birthday?

1. (modal auxiliary verb, defective, informal) May; to be permitted or enabled to.

You can go outside and play when you’re finished with your homework.   Can I use your pen?

1. (modal auxiliary verb, defective) To be possible, usually with be.

Can it be Friday already?

1. ca.1360-1387, William Langland, Piers Plowman

I can no Latin, quod she.

1. William Shakespeare (1564-1616)

Let the priest in surplice white, / That defunctive music can.

Usage notes

1. For missing forms, substitute inflected forms of be able to, as:
   1. I might be able to go.
   2. I was able to go yesterday.
   3. I have been able to go, since I was seven.
   4. I had been able to go before.
   5. I will be able to go tomorrow.
2. The word could also suffices in many tenses. “I would be able to go” is equivalent to “I could go”, and “I was unable to go” can be rendered “I could not go”. (Unless there is a clear indication otherwise, “could verb” means “would be able to verb“, but “could not verb” means “was/were unable to verb“.)
3. The present tense negative can not is often contracted to cannot or can’t.
4. The use of can in asking permission sometimes is criticized as being impolite or incorrect by those who favour the more formal alternative “may I…?”.
5. Can is sometimes used rhetorically to issue a command, placing the command in the form of a request. For instance, “Can you hand me that pen?” as a polite substitution for “Hand me that pen.”

Sentence Examples

• We can stop right here if you want, Carmen.
• They can wait until Jonathan gets up.
• We can only do so much.
• Of course, if you prefer, we can wait until you come home from work and make it a fun family event.
• The unknown can be worse than reality, and she had no idea what to expect on the flight.

could

Use could in a sentence

verb

1. The definition of could is often used in the place of “can” to show a little doubt.
   1. An example of could is someone asking if they can help someone.
   2. An example of could is saying that something is able to happen if someone does something.

could – auiliary verb

1. can: he gave what he could give
2. used as a modal auxiliary in verbal phrases with present or future time reference, generally equivalent to can in meaning and use, with the following functions:
   1. expressing esp. a shade of doubt or a smaller degree of ability or possibility: it could be so
   2. expressing permission: could I go?
   3. forming the present conditional: it would help if he could wait
   4. forming the past conditional: he would have left if he could
   5. expressing or suggesting politely less certainty than can: could you wait?

could – aux.v.

Past tense of can

1. Used to indicate ability or permission in the past: I could run faster then. Only men could go to the club in those days.
2. Used with hypothetical or conditional force: If we could help, we would.
3. Used to indicate tentativeness or politeness: I could be wrong. Could you come over here?

could – Verb

simple past tense of can

Used as a past indicative.

Before I was blind, I could see very well.

Used as a past subjunctive (irrealis).

I think he could do it if he really wanted to.

I wish I could fly!

Used to politely ask for permission to do something.

Could I borrow your coat?

Used to politely ask for someone else to do something.

Could you proofread this email?

Used to show the possibility that something might happen.

We could rearrange the time if you like.

Used to suggest something.

You could try adding more salt to the soup.

could

Variant of can

auxiliary verb

could

1. know(s) how to
2. am, are, or is able to
3. am, are, or is likely or at all likely to: can that be true?
4. have or has the moral or legal right to
5. Informal am, are, or is permitted to; may

Sentence Examples

• The lifestyle would be culture shock enough, but there were so many other things… family squabbles, gender commitments… things he had been foolish enough to believe he could escape so many miles away and in such a different lifestyle.
• It wasn’t something he could protect them from, though.
• When he told her that surrogacy would give them the opportunity to time things so she could breast feed, her expression confirmed his observation.
• With surrogacy, they could follow the pregnancy with ultrasounds, knowing that the baby was actually theirs.
• Only now could he realize what a mistake it would have been to marry Tessa.