We should advance step by step and not reach ______ what is beyond our grasp.
The Sahara Desert is almost _____ of the US.
---It’s a long time since I saw Marry.--- _________ her this afternoon?
—Why are you crying? Today is your birthday!—_______. I am so excited with so many friends surrounding me.
--- Haven’t seen you for ages! Where have you been ?--- I went to Ningxia and _______ there for one year, teaching as a volunteer.
When _________ our national flag _______, we feel our hearts full of pride and strength.