If one animal or person copulates with another, they have sex. You can also say that two animals or people copulate.
例句
During the time she is paired to a male, the female allows no other males to copulate with her...雌性与雄性配对时，雌性不允许其他雄性与之交配。Whales take twenty-four hours to copulate.鲸交配需要24小时。