Make the statements more polite. example: you`re not right.(think) - i don`t think (that) you`re right. 1. it wasn`t an explosion. (think) 2. they weren`t humans. (believe) 3. james hasn`t got an alibi. (think) |4. scientists can`t explain their disappearance. (believe)
2. I don't believe they were humans
3. I don't think James has got an alibi
4. I don't believe they can explain their disappearance.