Using : not have to / mustn't / can / could • george has traveled a lot. he speak four languages. • i can’t sing now but i sing very well when i was a child. • she will stay in bed till 10 o’clock this morning. because she go to work. • many students in turkey wear uniform when they go to school. • i’m sorry i couldn’t come yesterday. i work late. • you’ve been coughing a lot recently. you smoke so much. • you have a bad headache. so you go to bed early. • i can’t swim very far these days but ten years ago i swim from one side of the lake to the other. • you see the sea from our bedroom window. • it isn’t permitted to speak turkish during the lessons. so you speak turkish.