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.
Помогите пожалуйста!

Спасибо большое!

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.