英和和英

Can't do it

No, I'm afraid not.

To do my utmost, I can not do it

Unfortunately I cannot do it

No, I'm afraid not.

not capable of being obtained

not to be able to accomplish

I can't do that.

incapable of being passed

He is nothing of a scholar―no scholar （at all）.

I can't do that now.

It can't be!

He is not much of a scholar―not much of a one.

incapable of solution

I can do nothing

No, I can't.

Regretfully it is not possible.

so as to be incapable of moving

I've become impotent.

of a condition, intolerable

must not

to be worried that a certain thing is not accomplished

I wouldn't dare.

not able to be found

I don't know if I can do it.

to be unable to endure

I can do it, but I won't.

not capable of being retracted

I didn't think you had it in you.

You can't get blood out of a stone.