---Can you work out the maths problem? ---Sorry, I can ______ understand its meaning.
—_______ do you have a sports meet at your school?—Once a year.
The old man was _______ sad _______ say a word when he heard the bad news.
—Do you often help your cousin with his English?—No. He learns English _______.
_______ beautiful flowers they are!
—Did Alice sleep well last night?—No, she didn’t. She didn’t go to bed _______ 12 o’clock last night.