Question

25 

If you read a clock,you can know the time of day. But how did the early people know about the time?

We cannot see or hear time. We know it only when ifs passing. We know it has passed only when something (1) . In the real world,changes never stop. Some changes happen only once (2) others happen again and a- gain.

In early human history,people found that the changes of “light and darkness” seemed to (3) again and again. The sun rises in the east,producing (4) and goes down in the west,causing darkness. This ^ulight and dark-ness” was the first “time” for the early humans. We now call it one day.

People also saw the sun rise in the sky,sometimes (5 ) but sometimes lower.They counted the days that passed from the sun's highest position (位置) until it returned to that position. That was three hundred and sixty-five days. That's just one year.

Early humans also noticed changes of the moon. (6) used the changing faces of the moon to tell time. The moon was “full” when its face was bright and round. The early humans counted how many times the sun appeared(7) full moons. They learned that this number always remained the same—about twenty-nine. Twenty-nine suns equaled (等于) one moon. We now know this is one (8) .

In this way,we humans get the time of day,month,year and so on.

Answer 1

25. (l) changes (2) but/while (3) happen (4) light (5 ) higher (6) They (7) before (8)month