If someone condescends to do something, they agree to do it, but in a way which shows that they think they are better than other people and should not have to do it. 屈尊
verb [vi. 不及物动词]vi. 屈尊;俯就;(对某人)表现出优越感
When he condescended to speak, he contradicted himself three or four times in the space of half an hour. 当他屈尊讲话时,半小时内有三四次前后矛盾。