I seriously doubt I'd be able to...

I will no doubt be promoted to a more...

There may be doubt as to whether a given function is a governmental function.

His independent judgement is not to be doubted.

I doubt I'll be able to convince Washington.

Maybe. I doubt we'll be able to prove it, though.

I doubt we'll be able to prove it, though.

I doubt we'd be able to get you bail.

But, uh, I doubt they'll be able to.

Oh, I doubt they'll be around to collect.