He used to _______ up late, now he is used to _______up early.

―________ will you take the entrance examination?― In twelve days.

There are many shops on        sides of the street.

This is _______ important book. It helped me a lot in ________ old days.

 ---- Could you tell me how to write an application letter?  ---- With pleasure. Remember that the letter should be written in the formal _______.