In my pencilbox, ______ a pen, two pencils and three rulers.
There are ________ students waiting in the hall, ________?
You should keep the window _________ because the room is so hot and damp.
If you don’t know the word, you can _________ in the dictionary.
It is not ______ that everyone will be able to be famous persons.
They ________ often _______to be careful before _______the road.