Some researchers are finding that daydreaming may be important to ______ mental health and it is ______ good means of relaxation.
All the photographs in this book,stated otherwise, date from the 1950s.
—Can I call you back at two o’clock this afternoon? —I’m sorry, but by then I______ to Beijing. How about five?
I______ thank you too much for all your help to my son while we were away from home.
If he takes on this work, he will have no choice butan even greater challenge.
—The trip shouldn’t take more than an hour. —_______.it is at least two hours.