Look at ______ book on the desk . Is it ______ useful one ?—Yes, it is . In the book there is much advice on how to learn math well.

He jumped to his feet, thinking that the planes were going to ________.

(2013 .常州)- How soon will you start your journey?- I’m not sure. I haven’t decided_______.

He is a very hard-working student．—．As far as I know, he often burns the midnight oil．

I’m proud_____ our great country.[ ]