eight days, the eighth day

I read a book.

私は本を読みます

I read a thick book.

私は厚い本を読みます

I read a thick book in the living room.

私は居間で厚い本を読みます

I read a thick book in the living room before bed.

私は寝る前に居間で厚い本を読みます

I read a thick book in the living room before bed for eight days.

私は八日間寝る前に居間で厚い本を読みます