请问“let's open our books"."our books”是主语还是“books”是主语?

请问“let's open our books"."our books”是主语还是“books”是主语? Let's open our books _____ page 89 .填介词 let is open our books and turn_____page 89 填介词 为什么是这个介词? half of the books 做主语是单数还是复数 英语句子填介词can you read lesson2 lesson5?let`s open our books pag to,take,classroom,let‘s,books,our,these 儿童图书英语是children books还是children's books a library of 6000 books主语是哪个 our books are __________theirs. it's time for class .let's （-----）and take out our books.A.s how many books do you want?一句中you是主语?books是宾语?how many是宾补?do our books must be taken care of by us,还是our books must be ta