阅读理解。
Do you know that you can use your watch as a compass (指南针) on a sunny day? Take a watch and
point the hour-hand in the direction (方向) of the sun. Imagine a line which runs from the center of the watch
through a point half-way between the hour-hand and number one. This line will surely point south.
If you know astronomy a little, you will understand why this works. In the northern half of the earth, the
sun is in the south at noon. In Russia, the real noon is one o'clock. If at that time we point the hour-hand at
the sun, the hour-hand and number one will point south. That is why you must imagine a line which will run
from the center of the watch through a point half-way between the hour-hand and number one. It will point
south. If you are in the southern part of our planet, you must point number 12 at the sun. The line which you
can imagine between number twelve and the hour-hand will then show south.
1. When we carry out this experiment in the northern part of the earth, we should point _____ at the sun. [ ]
A. number 12
B. the minute-hand
C. the hour-hand
D. number one
2. The passage tells us that we can use a watch on a sunny day _____. [ ]
A. to study the weather
B. to show direction
C. to enjoy ourselves
D. to keep good time
3. If you are in Australia, which of the following is the right way to show north? [ ]
A. 
B. 
C. 
D. 
4. What's the best title for this passage? [ ]
A. Your Watch Becomes a Compass
B. An Interesting Watch
C. The Story of a Watch
D. The Sun and a Watch
