5, If the weather permits, we may go camping at the weekend.

=> If the weather permits: Nếu thời tiết cho phép.

6, After we had replaced the flat lyre with a new one, we went on driving to the countryside.

7, Having to dine with his superiors makes Bob feel uneasy.

8, On coming back home, we realized it had been broken into.

9, Having introduced my guests to each other, I made a long speech on the current changes in the computer technologies.

Giải thích ngữ pháp câu 6->9: Having done sth, S + Ved2 => After S + had done sth, S + Ved2: Sau khi đã làm gì thì làm gì.

5 If the weather permits, we may go camping at the weekend.
ĐK LOẠI 1: S+ V(s,es), S+ will/ can/ may+ V.
6 After we had replaced the flat lyre with a new one, we went on driving to the countryside.
Having V-p2 sth, S+ V-p2. = After S+ had V-p2 sth, S+ V-p2.
7 Having to dine with his superiors makes Bob feel uneasy.
After S+ had V-p2 sth, S+ V-p2. =  Having V-p2 sth, S+ V-p2.

8 On coming back home, we realized it had been broken into.
9 Having introduced my guests to each other, I made a long speech on the current changes in the computer technologies.
After S+ had V-p2 sth, S+ V-p2. =  Having V-p2 sth, S+ V-p2.