Do you have a good sense of direction？If not, please take with you a compass. But if you forget to take a compass, you can still find your way during the trip.
Suppose you are hiking with your family somewhere in the mountain in Dan Xia Mountain, you need to find the direction of south to find your way back. But none of your family members can read the map and actually knows where the family is. Never mind. The sun is shining and it's still morning. If you don't know the exact time，you can still find out where south is, but you'll need to be patient.
①Find a straight stick and put it in the ground in a place where you can mark its shadow.
②Try to put the stick as vertically (垂直) as you can. You can check this by making a simple plumb line (铅锤线) with a piece of string (绳子) and weight. You haven't got any string? Ok, use a thread from your clothes with a button tied at the end to act as a weight.
③After the stick is put vertically, you can see its shadow on the ground. Mark the end of the shadow.
④Wait about half an hour and mark the end of the shadow again.
⑤Keep doing this until you have made several marks.
⑥The mark nearest the stick will show the shortest shadow when it is midday，because at that time the sun is highest in the sky and pointing to the exact south.
⑦Pick a point in the distance along the line between the shortest shadow and the stick.
⑧That point is south of where you are.
⑨Now you can turn the map, like you did before, and find which way you should choose for traveling.
①It is a fine day and the sun is shining brightly.
②You are travelling with your family.
③You have a straight stick, a piece of string and a button.
④You mark the shadow every half an hour .
⑤You check the marks on the stick.
