Complete the conversation with one word in each gap.

Anne
Have you seen that documentary about pollution? We have to think seriously about it or things will be much worse in the future.

Vicky
I haven't seen it, but I agree. We need to think before building nuclear power stations 2. t____ again!

Anne
Well that's true, but there are other problems. We need to think 3. b___ and look at the whole picture.

Vicky
Anne, if you imagine people are going to do that, think 4. a___ ! Not everyone is interested in environmental problems.

Anne
Well, they're wrong. We must think 5. a_________ and try to reduce pollution for future generations. ​