Don’t leave the water ______ while you brush your teeth.
As your spoken English gets better, so ___ your written English.
I have only one day left ___ traveling to Kunming and then flying back home.
This is our contribution to ________ world of the 21st century, ________ world of independence and mutual understanding.
—She was late for the party. —That’s _________she had forgotten the exact time.
It_________ to me that I should pay a visit to my friend Jane.