Because is a subordinating conjunction. It shows the cause. So is a coordinating conjunction. It shows the effect.
We can combine two clauses using because and so.
Study the example given below.
Susie didn’t attend the party. She was not invited.
We can combine these two clauses in two different ways.
Susie didn’t attend the party because she was not invited.
Susie was not invited, so she did not attend the party.
1. He was lazy ..................... he did not study well.
2. I could not talk to him ...................... he was busy.
3. He was ill .......................... he did not attend school for a week.
4. He was sick ..................... they took him to hospital.
5. The teacher asked him to go out ....................... he misbehaved in the class.
6. We left the windows open .......................... it was warm.
Answers
1. He was lazy so he did not study well. / He did not study well because he was lazy.
2. He was busy so I could not talk to him. / I could not talk to him because he was busy.
3. He was ill so he did not attend school for a week. / He did not attend school for a week because he was ill.
4. They took him to hospital because he was sick. / He was sick so they took him to hospital.
5. The teacher asked him to go out because he misbehaved in the class. / He misbehaved in the class so the teacher asked him to go out.
6. It was warm so we left the windows open. / We left the windows open because it was warm.