Put the words in the correct place in each sentence.

问题描述:

Put the words in the correct place in each sentence.
例句:Astronauts have been to the moon.(already)
Astronauts have already been to the moon.
1.They haven't been to Mars.(yet)
2.Many astronauts have visited the space station.(already)
3.The spacecraft has reached Mars.(just)

1.They haven't been to Mars yet.
2.Many astronauts have already visited the space station.
3.The spacecraft has just reached Mars.