Find the mistakes. 1. i see the plane in a sky. - 2. a lot of factories pollute our the atmosphere. - 3. sun is a biggest star in our galaxy. - 4. people went to moon in the 20th century. !

1. I see a plane in the sky. - 
2. A lot of factories pollute our atmosphere. - 
3. Sun is the biggest star in our galaxy. - 
4. People went to moon in 20th century.

1I see a plane in the sky.
2a lot of factories pollute our atmosphere.
3The Sun is the biggest star in our galaxy.
4People went to the Moon in the 20th century.