Ex4: Put the verbs in brackets into the correct form:
1. If we (recycle) .....recycle..... more, we will help the Earth.
2. If I (be) .....won't..... you, I (do) .....will be..... that.
3. If people travel to work by bus, there (be) .....will be..... fewer car fumes.
4. We (save) .....will save..... thousands of trees if we don’t waste paper.
5. If we use water carefully, more people (have) .....will have..... fresh water.