Right form of verbs- 14
- Air (a) — (be) an important element of the environment. But it is constantly being (b) — (pollute) in many ways. We make a fire to cook food and (c) — (do) many works. This fire emits smoke which (d) — (contaminate) air. Vehicles pollute air to a great extent by (e) — (burn) fuel. Air pollution also (f) — (happen) when coal and oil (g) — (burn). Mills and factories can be (h) — (hold) responsible for this pollution. It is high time we (i) — (check) air pollution. Otherwise, we (j) — (suffer) a lot.
Answer: (a) is (b) polluted (c) do (d) contaminates (e) burning (f) happens (g) are burnt (h) held (i) checked (j) will suffer