=>
1. Na woke up late, so she didn't have time for breakfast.
Na woke up late. Therefore, she didn't have time for breakfast.
2. It was hot because Nga turned on the air conditioner.
Nga turned on the air conditioner. Therefore, it was hot.
3. Nam is sick today, so he won't go to school.
Nam is sick today. Therefore, he won't go to school.
4. Hoa worked hard, so she passed her exam.
Hoa worked hard. Therefore, she passed her exam.
5. The camera didn't work, so Mr.Robinson took it back to the shop.
Mr.Robinson took the camera back to the shop because it didn't work.

1)

Na woke up late, so she didn't have time for breakfast.

Na woke up too late. Therefore, she didn't  have time for breakfast.

2)

it was  hot. Therefore, Nga to turn on the air conditioner.

Nga turn on the air conditioner because it was hot.

3)

Nam is sick today, so he won't go to school.

Nam issick today ; therefore: he won't go to school.

4)

Hoa worked hard, so she passed her exam.

Hoa worked hard. Therefore, she  passed her exam.

5) 

The camera didn't work, so Mr Robinson took it back to the shop.

Mr Robinson took the camera back to the shop because it didn't work.