The time he has devoted in the past years _____________ the disabled is now thought to be ________ great value __________ him.
Ms Liu likes wearing formal clothes, but his sister usually dresses ________.
To keep the air fresh during the night, I often sleep with the windows on ________ it’s really cold.
Renmin Road is always crowded with traffic and people, it’s one of the _______ streets.
--- ____________________. ---The same to you!
Ok, class! Time is up! Please ________ your exam paper to the monitor!