sex

性行为、做爱、性爱

They talked openly about when to have sex for the first time.

他们坦率地谈到什么时候第一次发生性行为。

性别

The form asks for your age, sex, and place of birth.

这份表格要填年龄、性别和出生地。

性、情欲

The movie was criticized for using sex to sell tickets.

这部电影因为用性来卖票而受到批评。

鉴别性别专业

Workers at the hatchery sex the chicks within a day.

孵化场的工人会在一天内鉴别雏鸡的性别。