改错:1.There is some rubbish on the floor.Could you pick up it

改错:1.There is some rubbish on the floor.Could you pick up it ,please?___.
改错:
1.There is some rubbish on the floor.Could you pick up it ,please?___.
2.Could I go to visit Mr Li?No,you couldn't.You must finish your homework first.____.
3.The school provided the students for food and water.____
4.We should keep our classroom cleaning.___
5.They are both clever,but neither of them know the answer to the question.____