瑞士 (Ruìshì) is the Chinese name for Switzerland. It is used as a proper noun and can modify other nouns to indicate Swiss origin or nationality.
我哥哥去年去瑞士旅游了,说那里的风景太美了。
wǒ gē ge qù nián qù ruì shì lǚ yóu le, shuō nà lǐ de fēng jǐng tài měi le.
My older brother traveled to Switzerland last year and said the scenery there was incredibly beautiful.
瑞士手表在全世界都很有名。
ruì shì shǒu biǎo zài quán shì jiè dōu hěn yǒu míng.
Swiss watches are famous all over the world.
她的男朋友是瑞士人,会说四种语言。
tā de nán péng yǒu shì ruì shì rén, huì shuō sì zhǒng yǔ yán.
Her boyfriend is Swiss and can speak four languages.