The two kinds of cellphones differ __________ shape, but they are similar __________ each other in some functions.
About _______ of the surface of the earth _______ covered with water.
It will take _______ time to finish the work.
--- How long will your stay here ? ---For ________ .
When he moved to Germany in ______ , he was already in _______ .
My brother lives in ______ on ______ floor.