Carl Sagan suggested striking Venus with large asteroids, in an attempt to expel the inhospitable atmosphere away from the planet.
Probably not.
No. There is no surface to terraform.
Terraform - album - was created in 1998.
I'm having difficulty with the definition of terraform... It would be no easy task to terraform the Earth's Moon.
Yes. Carl Sagan proposed back in 1993 that we should strike Venus with large asteroids, in an attempt to eject the inhospitable atmosphere away from the planet.
Terraform it.
Some people think it would be a good idea to terraform the moon, because we were not able to take care of our own planet.
Terraform.
For humans to live on Venus would require floating cities or massive bunkers. Almost all water and oxygen would have to be brought there, as very little exists in usable forms. Theories to terraform Venus would require energy sources, materials, or technologies beyond those available in the foreseeable future. Earth-like, carbon-based lifeforms could not exist on the surface, and likely never did.
No official plans by any space organizations have been made to terraform the moon of the Earth; in fact it is considered impractical by many unless the mass of the moon is increased greatly.
You don't terraform plants, so I'll assume its a typo and you meant planets. The answer is none of them can be terraformed, terraforming is purely hypothetical and there is no means to test or prove anything whatsoever at this time.
Possibly. It would take generations to accomplish though.