our class will not be taught by Mr.Brow => the student will have written many compositions => the students must do this exercise in class => the poster has been done by Mai and Ly

Mr. Brow won't teach our class.

Bị động với thì tương lai đơn → câu chủ động: S+ will/won't+V_inf + O

Many compositions will have been wirtten by the student.

Câu bị động: S+ will/won't + have been + V_ed/PP.2+ (by O)...

This exercise must be done in class by the students.

Modals:

S + modals + Vinf

(Modals: can/ could/ will/would/ should/ must/ ought to/ may/ might/ used to/ be going to/ have to)

S + modals + be + PP.2 +địa điểm+ by O + thời gian

Mai and Ly has done the poster.

have/has been + V_ed/PP.2 ⇒ have/has + V_ed/PP.2