This poem can remind of the good old days___ studied in this beautiful school.

--Would you like this pair, or that pair? ---___ will do.

Sarah decides to move to Hainan because she thinks that the air there is much fresher than ___ here.

Today’s world is changing rapidly, making _____ necessary for us to continue learning otherwise we can’t keep up with the time.

Culture shock often comes as _____surprise to most people the first time they experience it in one form or        ..