Structure:

Noun 1 + 是 + Noun 2

Meaning:

This is equivalent to “Noun 1 is Noun 2” in English.
Chinese does not conjugate verbs. That is, the form of the verb is the same no matter who is doing it. In this case, it is always 是 and never changes. As you can see, it’s easy to form simple sentences expressing to be in Chinese.

Examples:

Noun 1                 Noun 2                 是                                   Translation                                                                      

她                            是                      学生             。               She is a doctor.

我                            是                      学生              。               I am a student.                                                                

这                            是                       书                。               This is a book.                                                                 

那                            是                        杯子            。              That is a cup.

他                            是                        老师            。               He is a teacher.