He . documents by the time the boss came.

В данном предложении посмотрим на время, да и на само задание:

Скажем, что в данном случае нет отрицания и тут время Past Perfect!

Значит получаем такое предложение:

He  had prepared documents by the time the boss came.

1) i will ride my bike tomorrow.

2) my grandma got two letters yesterday/

3) they were in the country last summer.

it was great.i spent this time with my friend.we went for a walk.we watched tv.we ate cake,of couse.we went to the cinema and we watched interesting film.but on the 31 of december i was with my parents and grandparents.we celebrated new year together.i played computer games.i went to the zoo.i went to the art museum.i went to the cafe and did other funny things.so,my winter holidays were grade.