----How often do you _________ the dictionary when you are doing reading? ----Not very often. Only when I find it is necessary.
In the exam , the you are, themistakes you’ll make.
—When shall we start? —Let's _____ the time for the trip. What about 8:30? Is that all right?
Don’tspend time beating ona wall, to change it into a door.
One of the most important questions they had to consider was ______ of public health.
You'd better not ring me up between 9 and 10. I________ an important meeting then” Dr. Lee said.