A: How are things going?

B: I can’t complain.

A: What’s the weather like on your holiday?

B: Oh, can’t complain.

Note: This is used to say that a situation is satisfactory, even though there may be a few problems. It’s a casual response to questions like “How are you?” or “How’ve you been?” This modern-sounding phrase comes from Britain in the mid-19th century.