過去進行式 (Past Progressive Tense)
What were you doing at nine o'clock last night?
I was riding my bike at nine o'clock last night.
The children were staring at us with huge eyes.
While I was eating dinner, the telephone rang.
My boyfriend was waiting for me when I got off the plane.
Andy was cooking dinner when I arrived.
I was watching TV when she called.
What was he doing when the earthquake started?
While we were having the picnic, it started to rain.
上面這些例子，讀者不難發現都有從屬連接詞 when 與 while 來連接兩個子句而形成複句。通常 when 描述過去發生的事，後面跟著過去時式， 而 while 強調過去的一段時間所發生的事，後面跟著過去進行式。
They _______ when you arrived.
(A) are studying (B) were studying
- When she called me, I am playing the piano and did not hear the phone.
- When she called me, I was playing the piano and did not hear the phone.
- Tom was wanting to be a scientist when he was a child.
- Tom wanted to be a scientist when he was a child.
- She was hearing a loud bang while she talked to her mom.
- She heard a loud bang while she was talking to her mom.
The waiter was taking my order when the lights went out.
My order was being taken by the waiter when the lights went out.
Was she being stalked by somebody? That's our big question.
過去進行式夾帶著 always 或 constantly 通常表示負面的意思。
Jeff was always coming to class late.
She was always complaining; nothing satisfied her.
He was constantly changing his mind.