Optimistic sentences:

I think it will be a better place. (3 linijka)

I'm sure scientists will find a way to protect the environment with technology. (6 i 7 linijka)

I hope so. (8 linijka)

I hope people will save water and use green energy. (8 linijka)

I think they will. (10 linijka)

But I think we'll go on holiday to space and to the Moon. (12 i 13 linijka)

...but I agree with you. (14 linijka)

I don't believe humans will have to work hard in the future. (16 linijka)

I think scientists will build robots that look like people and the robots will work for us. (19 i 20 linijka)

 

Pessimistic sentences:

I don't think it will be. (4 linijka)

I believe we'll destroy the environment. (4 i 5 linijka)

I don't think it will happen soon. (12 linijka)

It sounds unrealistic... (14 linijka)

I don't believe that. (21 linijka)