1. Công thức

(+) S + was / were + V-ing

(-) S + was / were + not + V-ing

(?) was / were + S + V-ing?

Ví dụ:

I was working.
She wasn’t watching TV.
Were they playing football?

2. Cách dùng

2.1 Hành động đang xảy ra trong quá khứ thì bị hành động khác chen ngang

(“Khi đang… thì…”)

Cấu trúc 1:

S1 + was/were + V-ing + when + S2 + V2

I was watching TV when she came home.

 

Cấu trúc 2:

When + S2 + V2, S1 + was/were + V-ing

When she came home, I was watching television.

 

2.2 Hai hành động xảy ra đồng thời trong quá khứ

Cấu trúc 1:

S1 + was/were + V-ing + while + S2 + was/were + V-ing

Martha was watching television while John was reading a book.

 

Cấu trúc 2:

While + S1 + was/were + V-ing, S2 + was/were + V-ing

While John was reading a book, Martha was watching television.

 

Cấu trúc ít dùng hơn:

While + S1 + was/were + V-ing, S2 + V2

While John was reading a book, Martha watched television.

 

2.3 Hành động đang xảy ra tại một thời điểm xác định trong quá khứ

Martha was watching TV at seven o’clock last night.

What were you doing at one o’clock this afternoon?

Henry was eating a snack at midnight last night.

 

3. Dấu hiệu nhận biết

• when
• while
• at + giờ cụ thể (at 7 p.m, at midnight, at that moment)
• at that moment
• all + thời gian (all morning, all day, all night)
• this time + mốc quá khứ (yesterday at 5, last night at 10, this time last year)

 

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Exercises – Bài tập