是 对用英语怎么说

"是" is a Chinese word that means "to be" or "is" in English. It is used to indicate the identity or existence of something or someone.
For example:
他是学生。 (Tā shì xuéshēng.) - He is a student.
这是一本书。 (Zhè shì yī běn shū.) - This is a book.
In Chinese, "是" is used in various grammatical constructions, such as with a verb or adjective to indicate that someone or something is doing something or has a certain quality. For example:
他是在唱歌。 (Tā shì zài chànggē.) - He is singing.
这是一个好主意。 (Zhè shì yīgè hǎo zhǔyì.) - This is a good idea.
In addition to being used as a verb, "是" can also be used as a conjunction to introduce a clause that explains or clarifies something. For example:
他很帅，是因为他健康饮食。 (Tā hěn shuài, shì yīnwèi tā jiànkāng yǐnshí.) - He is handsome because he has a healthy diet.
她是我的朋友，我们在一起学习。 (Tā shì wǒ de péngyǒu, wǒmen zài yīqǐ xuéxí.) - She is my friend and we study together.
"是" is a very common and important word in Chinese, and it is used in many different contexts. I hope this information is helpful!