Kate’s little brother kicked the ball to the river; she took great trouble to get in _______the river.
Don’t stop _______ you meet with a word you don’t understand while reading.
While we are developing agriculture and industry, we must prevent the earth ______.
When _______ help, one often says “Thank you.” or “It is kind of you “
Frank insisted that he was not asleep______ I had great difficulty in waking him up.
_______seems to have been a strong competition in China for school leavers to enter college or university.