Module 5. Modern world » Стр.51 (C)

Choose a, b or c. 1–c; 2–c; 3–b; 4–b; 5–c; 6–a. 1. We c. mustn't throw rubbish in rivers because the fish will die. 2. Ryan got up very early yesterday because he c. had to be at the doctor’s at 7 o'clock. 3. It's cold, so you b. don't have to wait for me at the entrance. I'll meet you inside the art gallery. 4. You b. can't swim here. It's dangerous! 5. Martha can't see well, so she c. has to wear glasses. 6. Iris had an accident. She a. must go to the doctor.