Numeral + 名 + 成人
The noun 成人 (chéngrén) means "adult" and refers to a person who has reached the age of maturity. It is used in formal contexts and contrasts with 儿童 (children) or 未成年人 (minor).
这部电影只适合成人观看。
zhè bù diànyǐng zhǐ shìhé chéngrén guānkàn.
This movie is only suitable for adults.
在中国,十八岁以上算成人。
zài Zhōngguó, shíbā suì yǐshàng suàn chéngrén.
In China, people eighteen and older are considered adults.
游泳池分成人区和儿童区。
yóuyǒngchí fēn chéngrén qū hé értóng qū.
The swimming pool is divided into an adult area and a children's area.