to prep.对于；为了；(表示方向)到；向；(表示间接关系)给adv.（表示方向）去；（门）关上
双语例句
The periodic state of sexual excitement in the female of most mammals, excluding human beings, that immediately precedes ovulation and during which the female is most receptive to mating; heat. (雌性动物的)动情，动情周期大多数哺乳动物(包括人类)的雌性产生的周期性的性冲动，在此期间内雌性具有排卵的优势，所以该期间最适合性交; 刺激
