It remains to be seen________North Korea will remain stable under its new young leader.

 — You look sad. ____?— Oh, my grandmother’s very ill.

 Safety in school has been of great concern because of frequent reports about accidents _______ students got injured or killed while in school .

 —I read the 21st Century Senior 2 Edition every day.  —_____ no wonder that your vocabulary is so large.

---He seems to be a teacher.---______. He has been a teacher for 20 years.