3 Nam sorried that he couldn't see the music concert the night before ( reported speech: câu tường thuật)

4 If my brother worked harder, he could succeed in his job ( có thể dùng câu đk loại 1, mình đang dùng câu đk loại 2 vì thấy phù hợp với ngữ cảnh trong câu )

5 It is ( very) dangerous to ride a motorcycle without wearing helmet 

6 If we keep the environment clean, we will live a happier and heathier life ( câu đk loại 1)

7 Mr Nam got up late this morning, so he missed the first bus 

8 I suggesr helping the elderly people and war invalids with their chores 

3. Nam sorried that he couldn't see the music concert the night before.
4. If my brother worked harder, he could succeed in his job.
5. It is very dangerous to ride a motorcycle without wearing helmet. 
6. If we keep the environment clean, we will live a happier and heathier life.
7. Mr Nam got up late this morning, so he missed the first bus.
8. I suggesr helping the elderly people and war invalids with their chores.