One of the students hasn’t prepared ____ lessons very well.
I shall never forget the day ________ Shen Zhou V was launched, ________ has a great effect on my life.
________ is known to everybody, Taiwan is a part of China. We must unify it.
October 15 th is my birthday, ________ I will never forget.
We won’t give up ______________we should fail ten times.
___________, Mother will wait for him to have dinner together.