Разберем упражнение, в котором нужно соединить две части предложения, используя "by the time" и Past Perfect.
She / cook dinner → her parents / come home
By the time her parents came home, she had cooked dinner.
The game / start → we / turn on the TV
By the time we turned on the TV, the game had started.
He / clean his room → his sister / wake up
By the time his sister woke up, he had cleaned his room.
The shop / close → they / arrive
By the time they arrived, the shop had closed.
The rain / stop → we / go outside
By the time we went outside, the rain had stopped.