Subject + 是 + Noun/Noun Phrase
The verb 是 (shì) functions as the Chinese equivalent of 'to be,' linking a subject to a noun or noun phrase. Unlike English, 是 is not used with adjectives — Chinese uses adjectives directly as predicates. For example, 这是最好的礼物 means 'This is the best gift.'
她是我最好的朋友。
Tā shì wǒ zuì hǎo de péngyǒu.
She is my best friend.
今天是星期三,不是星期四。
Jīntiān shì xīngqīsān, bù shì xīngqīsì.
Today is Wednesday, not Thursday.
这是我第一次来北京。
Zhè shì wǒ dì yī cì lái Běijīng.
This is my first time visiting Beijing.