I think this software is of little use to your work. It is really a ________ of money. 

Some people hold the view that the new machine is advanced, while others are still skeptical _____ whether it is of practical use.

In my opinion，the  boy really has   　 for oil painting.

 Last summer holiday we spent the ____ few sunny days on the seaside. 

 Chinese students are good at taking exams and you can’t imagine what they are willing to        to succeed.