A an end     B a saying    C a joke          D a pause<br/>

A the government B himself C a broker D the stock exchange<br/>

A the Wall Street Exchange B the New York Stock Exchange C the Curb Exchange D the U. S． Exchange

A The stockholder can sell his stock to anywhere at any time． B There were no stock exchange in England in the 1700's． C The price of stock is not stable． D The stockbrokers do the transaction without charging for the stockholders．<br/>

A the Wall Street B the stock exchange C the stock D the stockholder and stockbroker<br/>

A protecting children B assisting shepherds C helping hunters D herding cattle<br/>

A carried supplies B provided companionship C tracked prey D herded caribou (驯鹿)<br/>

A size B structure C temperament D appearance<br/>

A benefited animals other than dogs B served man C helped other dogs D contributed to medical knowledge

A it protects him against the harmful rays from space B it provides sufficient light for plant growth C it supplies the heat necessary for human survival D it screens off the falling meteors