Complete the gaps with the correct forms of the verbs in

Complete the gaps with the correct forms of the verbs in brackets. First Conditional
If life expectancy increases (increase), people will have to (have to) work longer.
1 The air ___________ (be) cleaner if we ___________ (use) public transport.
2 If unemployment ___________ (go) up, I ___________ (look) for work abroad.
3 Solar panels ___________ (not/work) if the sun ___________ (not/shine).
4 If we ___________ (not/replant) forests, there ___________ (be) less oxygen.
5 We ___________ (not/be able) to drive if there ___________ (not/be) any petrol.