Ex 2:

1. Let's pay a visit to Huong Pagoda.

⇒ Why don't we pay a visit to Huong Pagoda?

2. Jane didn't go fishing yesterday because it rained heavily.

⇒ Because it rained heavily so Jane didn't go fishing yesterday.

3. His idea is different from mine.

⇒ His idea is not the same as mine.

Ex 3:

6. free time /Joe /doing /work /spent /most /at /his /local hospital /a /of /volunteer.

⇒ Joe spent most of his free time doing volunteer work at a local hospital.

1, Why don't we pay a visit to Huong Pagoda. ( cấu trúc Let's+V =Why don't we...)

2, It rained heavily, so Jane didn't go fishing. 

3, His idea is not the same as mine.

Ex3:

6, Joe spent most of his free time doing for a volunteer at a local hospital.

or Joe spent most of his free time work as a volunteer at a local hospital (xem giúp mình câu có bị lỗi ko ạ hay do mình lú :3)