A new iphone costs about _________of a second-hand one．

How can I apply for an online course? — Just fill out this form and we _______ what we can do four you

Chinese is ___ a useful language _____ more and more foreigners want to learn it.

happened to be no one in the building when the fire broke out.

It is said that the famous football star is now willing to play for______ would pay him three million dollars a year.