Mr and Mrs Jones were going on their vacation(假期) with their children, and they must arrive at the airport before 11:40 the next morning. “It takes us thirty minutes to get there in a car,” Mr Jones said, “so we must get ready before eleven o’clock. Don’t be late.”
At ten-fifty, all of them were busy doing something, but Mrs Jones wasn’t. She sat quietly in a chair in the garden and enjoyed the good weather.
Mr Jones and the children were surprised, but Mrs Jones said, “Don’t worry! Before I went to bed last night, I made all our clocks and watches twenty minutes ahead(提前). Now we can get to the airport early.”