閱讀短文，根據(jù)其內(nèi)容回答問(wèn)題。

　　You either have it, or you don’t－a sense of direction, that is．But why is it that some people could find their way across the Sahara without a map, while others can lose themselves in the next street?

　　Scientists say we’re all born with a sense of direction, but it is not properly understood how it works．One theory is that people with a good sense of direction have simply worked harder at developing it．Research being carried out at Liverpool University supports this idea and suggests that if we don’t use it, we lose it．

　　“Children as young as seven have the ability to find their way around,”says Jim Martland，Research Director of the project．“However, if they are not a11owed out alone or are taken everywhere by car, they never develop the skills．”

　　Jim Martland also says that young people should be taught certain skills to improve their sense of direction．He makes the following suggestions：

　　●If you are using a map, turn it so it connects with the way you are facing．

　　●If you leave your bike in a strange place, put it near something like a big stone or a tree．Note landmarks on the route as you go away from your bike．When you return, go back along the same route．

　　●Simplify the way of finding your direction by using lines such as streets in a town, streams, or walls in the countryside to guide you．Count your steps so that you know how far you have gone and note any landmarks to help you．

　　Now you need never get lost again!

1．Could some people find their way across the Sahara without a map?

_______________________________

2．When do we get a sense of direction according to the passage?

_______________________________

3．Why don’t some people have the sense of direction?

_______________________________

4．What does the underlined word"landmarks"mean in English?

_______________________________

5．What does the passage mainly talk about?

_______________________________