Act 1. Circle the letter A B C or D to indicate the correct answer.
1. Water pollution is the________ in the lake.
A.contaminating B.contaminate C.contaminated D.contamination
2. By the time they got to the cinema, the film________
A.started B.had started C.starting D.starts
3. The train No 5 ________ for Ha Noi at 5'o clock tomorrow afternoon
A.leaves B.is leaving C.has left D.will leave
4. He often drinks coffee, but today he_______ tea
A.is drinking B.drink C.drank D.drinks