everyone

When we replace everyone, which word do we use, they or he?
Is the sentence" Everyone in the class has a desk to put your books in." right?

I think we should use ‘they’ instead of ‘he’.

In my opinion the Following sentence is correct:

Everyone in the class has a desk to put their books in.

When we replace everyone, which word do we use, they or he?
Is the sentence" Everyone in the class has a desk to put your books in." right? – No.

Formal: Everyone has a desk to put his or her books in.
Informal: Everyone has a desk to put their books in.
The wise choice: All of you/them have desks to put your/their books in.