In the past, ice used to ______ used to ______ the air in a room.
John rushed out in a hurry, _____ the door _____ .
Please come to visit me if _________________.
---Why do you look so sad? ---There are so many problems_______.
Even the __________ doctor couldn’t cure him __________ his deadly disease.
As we all know, the father __________ for the spoilt child.