Đặt câu hỏi dựa theo những từ được gạch chân trong câu 

`1.` When was Mike reading the document?

`-` when : khi nào `-` hỏi thời gian

`2.` Where was Sarah  waiting for him?

`-` where : ở đâu `-` khi nào

`3.` What were the students talking about?

`-` what : cái gì

`4.` Who was writing a letter?

`-` who : ai `-` hỏi người

`5.` What was Lisa looking for?

`____________________`

`***` QKTD:
`(+)` S + was/were + V_ing + O

`(-)` S + was/were + not  + V_ing + O

`(?)` Was/were + S + V_ing + O?

`1` .What time was Mike reading a document `?`

`->` at six o'clock `->` hỏi lúc mấy giờ `->` dùng what time

`2` .Where was Sarah waiting for him `?` 

`->` in the park `->` chỉ nơi chốn `->` dùng where

`3` .What were the students talking about `?`

`->` American culture `->` chỉ 1 sự vật/thứ gì đó `->` dùng what 

`4` .Who was writting a letter `?`

`->` the secretary `->` chỉ người `->` dùng who

`5` .What was Lisa looking for `?`

`->` her necklace `->` chỉ 1 sự vật/thứ gì đó `->` dùng what 

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`=>` Cấu trúc QKTD :

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

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

`(?)` Was/were `+` S `+` V-ing