So difficult ________ it to live in an English-speaking country that I determined to learn English.

Sixteen –year-oldsshould ____ to drive.

We ________ hope you will get a nice result on the National Games-Thank you very much[ ]

He has been in the USA .

－What do you think is the _________ of mobile phones, Peter －I think it’s very convenient for us to keep in touch with each other at any time.