THÌ QUÁ KHỨ ĐƠN

1. To be: 

S+Was/Were + Adj/ Noun

Ex:

- She was a charming actress

- They were renowned scientists

2. Verbs:

S+V quá khứ

Ex: 

- I started studying English when I was 6 years old

- They invented the light bulb on their own

Last night/ year/month; yesterday, 2 years ago; in 1999...

THÌ QUÁ KHỨ TIẾP DIỄN

1. Công thức chung

S+Was/Were+V-ing

Ex:

- I was playing sports when my mom came home

- She was reading at this time last night

At this time last night; at this moment last year; at 8 p.m last night; while...