=>

1. This house was built by my grandfather 40 years ago.

-> bị động QKĐ was/were V3/ed

2. We didn't enjoy our camping holiday due to the awful weather.

-> due to N/Ving: do

3. We can't see the stars at night because there is too much light pollution.

-> because S V: bởi vì

`1. ` This house was built by my grandfather `40` years ago 

- Bị động quá khứ đơn : S + was / were + ( not ) + V3 + ( by O ) 

- This house - danh từ số ít ` -> ` dùng be là was 

` 2. ` We didn't enjoy our camping holiday due to the awful weather

- Due to + N / V-ing : do

- Tính từ + danh từ , awful weather : thời tiết tồi tệ 

` 3 . ` We can't see the stars at night because there is too much light pollution 

- Because + mệnh đề ( S + V ) : Bởi vì ...