`1.` My friends and I cleaned up the streets in our neighbourhood when we were small every summer.

`@` QKĐ + when + QKĐ

`@` QKĐ: S+ V2/V-ed+O

`2.` My aunt often donates money to chariable organisations.

`@` HTĐ (DHNB: often):

S+ V(s/es)+O

`3.` They started this project with the aim of helping homeless people return to the community and enabling them to rebuild their lives.

`@` the aim of N/V-ing: mục đích  

`4.` Our campaign attracted over 1000 volunteers all over the world last year.

`@` TTSH + N

`@` QKĐ (DHNB: last year):

S+V2/v-ed+O

`5.` People can sign up online to become a member of our charity organisation.

`@` can + V-inf: có thể làm gì

`-` sign up (v): đăng ký

`6.` Volunteering provides many benefits to both mental and physical health.

`@` V-ing đứng đầu câu đóng vai trò làm chủ ngữ

`@` many + N-số nhiều: Nhiều ...

`@` both A and B: Cả A và B 

`7.` Doing volunteer work is an opportunity to gain experience and skills.

`@` V-ing đứng đầu câu đóng vai trò làm chủ ngữ

`@` to + V-inf: Để ... `->` Chỉ mục đích

`8.` How about donating our old books, toys and clothes to charity?

`@` How about + V-ing+O?

`->` Rủ ai đó làm gì cùng mình

`9.` Did the organisation provide shelter for the children?

`@` QKĐ:

(?) Did+S+V-inf+O? 

`10.` Do you remember when you first volunteered?

`-` HTĐ: (?) Do/Does+S+V-inf+O?

`color{lightgreen}{Vanie}`

`1`. Every summer when I was small, my friends and I cleaned up the streets in our neighbourhood.

`2`. My aunt often donates money to charitable organisations.

`3`. They started their project with the aim of helping homeless people rebuild their lives and enabling them to return to their community.

`4`. Our campaign attracted over 1000 volunteers from all over the world last year.

`5`. People can sign up online to become a member of our charity organisation.

`6`. Volunteering provides benefits to both mental and physical health.

`7`. Volunteering is an opportunity to gain work experience and skills.

`8`. How about donating our old books, toys, and clothes to the charity?

`9`. Did the organisation provide shelter for the children?

`10`. Do you remember when you first volunteered? 

________________________________________________________________________

Công thức thì quá khứ đơn

(`+`) S + V-ed + ...

(`−`) S + didn't + V-inf

( `?` ) Did + S + V-inf .... ?

`***` Dấu hiệu nhận biết: Yesterday, ago, last,...

`+` Khoảng thời gian trong quá khứ