异性 (yì xìng): 이성

She usually doesn't dare to talk to the opposite sex, but this time, in order to finish the group report, she took the initiative to ask a male classmate from her group to discuss it together.

The company's new rule prohibits employees from being alone with opposite-sex colleagues in the meeting room during office hours, to avoid causing misunderstandings.

At speed-dating events, participants are usually arranged to talk with several people of the opposite sex in turn, so as to find a suitable partner.

He is introverted and rarely takes the initiative to attend gatherings with people of the opposite sex, so his friends always want to introduce him to potential partners.

It is very normal for adolescents to become curious about the opposite sex; parents should patiently guide them rather than strictly forbid it.