在学习英语的过程中，掌握不同的时态是非常重要的。今天，我们要练习的是过去简单时和过去完成时。过去简单时（Simple Past）用来描述过去某个确定时间发生的动作或存在的状态；而过去完成时（Past Perfect）则用来表示在过去某个时间点或动作之前已经完成的动作或存在的状态。通过对这两种时态的对比练习，我们可以更好地理解它们的用途和区别。
本次练习包括了15个句子，每个句子中都有一个空格，学生需要根据上下文的提示，填入正确的动词形式。这是一个很好的机会来测试和巩固你对过去简单时和过去完成时的理解和运用。练习后面有答案，你可以对照答案来检查自己的练习结果。
练习一：填入过去简单时或过去完成时的正确动词形式
By the time we arrived at the cinema, the movie *had started* (start).
I *visited* (visit) Paris three times last year.
She *had finished* (finish) her homework before she went to the gym.
We *did not see* (not see) any deer in the forest yesterday.
He *told* (tell) me he had lost his keys.
The children *were* (be) happy because they had won the game.
After Susan *had read* (read) the book, she gave it to her friend.
They *did not go* (not go) to the party last weekend.
Before the 19th century, nobody *had known* (know) about electricity.
When I was young, I *had* (have) a pet rabbit.
Last night, we *watched* (watch) an interesting documentary on TV.
By the time I got your message, I *had already left* (already leave) the office.
*Did* (Do) you enjoy the concert last night?
She *had never seen* (never see) such a beautiful sunset before that day.
After he *had eaten* (eat) dinner, he called his mother.
练习二：填入过去简单时或过去完成时的正确动词形式
She *saw* (see) him at the grocery store after she had finished shopping.
The train *had left* (leave) when we arrived at the station.
He *wrote* (write) an email before he went to bed.
Maria *had never heard* (never hear) of that musician before you mentioned him.
I *did not understand* (not understand) the lesson yesterday.
They *flew* (fly) to New York last summer.
Before 1990, he *had never traveled* (never travel) outside his country.
When I entered the room, everyone *was* (be) silent because the film had already started.
I *met* (meet) my best friend for the first time in high school.
By the time the firefighters arrived, the building *had been* (be) engulfed in flames.
The thieves *had escaped* (escape) before the police arrived.
Before we *reached* (reach) the top of the mountain, we had taken many breaks.
He *forgot* (forget) to lock the door when he left the house.
She *did not call* (not call) me last night, so I called her this morning.
Before last year, I *had not thought* (not think) about studying abroad.
