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 have to work hard to improve my english

2)joan doesn’t   have to go.she can stay here.

3)i’m   sorry   i’m late.i had to do the shopping.

4)i think the spacemen has known english.

5)does she have to read this rule?

6)tom doesn’t  have to use a computer.

7)you have to know english to understand people.

8)does mary have to help ann to study english?

9)what time do you have to get up?

10)has your teacher corrected your homework?  

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