"Can" and "Could" for ability. You can use "can" to talk about things that someone is able to do: I can speak Spanish and French, too! In the past, "could" is actually a little tricky. Sometimes …

Should I use "Can I", "Could I", or "May I"? A student sent me a question about how to ask for permission in English:

Could I push my appointment back to later that afternoon? The opposite is "pushing (something) up": Originally we were going to do it on the 21st, but I decided to push it up to the 19th.

You could have killed someone! The meaning is that, although you didn't kill anyone, there was a high chance of accidentally killing someone. One common use of "could have ___" is to …

The secret is that "could" is not really past tense. It looks like past tense, but it's secretly something different. It's the "unreal" aspect. In other words, it expresses something that's not …

If you strongly disagree with someone's opinion, you can say this: I couldn't disagree more. Of course, disagreeing with someone so clearly may start an argument so you should be careful …

Explanation of the English phrase "Can you do me a favor?": If you need to ask someone to do something for you which is extra work or a little annoying for that person, begin with "Can you …

This is a rather polite way to ask someone to do something. It's polite because the phrase "would you" is less direct than "Can you" or "Will you".

Explanation of the English phrase "Would it be possible to (do something)?": This is a formal and polite way to ask for something: Would it be possible to make an appointment for later today?

With a closer friend or acquaintance, it's more friendly to ask "Could you ___?": Could you pass me the salt? confirm that (clause) When you already know something, but you want to make …