I can vs I could

AnonymousIs this right:

I've done everything I could.

I did everything I can could.

As shown, both are correct.

CJ

So even though, have done is present perfect, it can still go with could?

And one last question:

Even though I wanted to, I couldn't.

Even though I wanted to I can't.

Even though I want to, I can't.

Even though I want to, I couldn't.

Which of these are right?

AnonymousEven though I wanted to, I couldn't.

Even though I wanted to I can't.

Even though I want to, I can't.

Even though I want to, I couldn't.

"I've done everything I can" is also correct.

So even though, have done is present perfect, it can still go

I have another question:

What about if I was going to answer a question like...

What is the best place you've ever been to?

Can you say: The best place I've ever been to was/is London?

or like

The best advice I've ever received was/is from
The best book I've ever reas is/was

Is it was/is or are both okay?

One more thing, is it.........

The biggest mistake I've ever made is/was......

Actually, your had them reversed.

AnonymousIve done everything I can could. Present verb -> use can

I did everything I could

is this right too?

You could dress it up if you want to.

I have another question:
What about if I was going to answer a question like...
What is the best place you've ever been to?
Can you say: The best place I've ever been to was/is London?
or like
The best advice I've ever received was/is from
The best book I've ever reas is/was
Is it was/is or are both okay?

And also can i say,
You could wear that if you want

Anon,

AnonymousThis is my approach toward your questions:

What is the best place you've ever been to?
Can you say: The best place I've ever been to was/is London?
Grammatically, the question is "what is the best place...?". So the a