—I’ve met him dozens of times, but I still don’t know his name.—I hope this won’t happen again.

 _______ the help of my teacher, I worked out the problem in the end.

------Could you please sweep the floor?------___________. I am busy looking after my sister.

_____ tallest student in the swimming club is _____ boy called Dale.

-- Drugs have done great harm to some people and their families.--Quite true, so we should ________ them.