1, The study of space was mainly carried out by astronomers using telescopes.

2, Humans also want more space to accommodate the world’s increasing population.

3, Yes, they have.

4, Within more than two decades, from the beginning of 1950s to 1970s, the two nations launched many of the milestones.

5, The cooperation in launching the International Space Station is the biggest achievement of the 21^st century.

1, I moved to a new town where trees are planted along the street.

Chúc bạn học tốt!!!

2, Humans also want more space to accommodate the world’s increasing population.

5, The cooperation in launching the International Space Station is the biggest achievement of the 21^st century.

Chúc bạn học tốt nhé!