Перепишите предложения, употребив глаголы в past simple в нужной форме, добавив соответствующие обстоятельства времени:
Mr. Brown writes a lot of letters
Our fax-machine doesn't work
We send letters every day
Do you know the answer?
We do not buy telephone equipment
This order is very important
They deliver all orders on time
We sell books to different countries