You can swim, can't you?

I think I've got a touch of fever.

Ken is busy now, isn't he?

You are busy now, aren't you?

I'm just a creature of habit, I guess.

"I heard that Tom and John are identical twins. They really do look alike, don't they?" "Yes, they really do look very similar. Even their parents say they get confused sometimes. Those two really are very similar, aren't they?"