7.Developing countries should adopt labour-intensive technologies to ____ their comparative advantage of abundant labour.

　　A.use B.exploit C.employ D.explore

　　8.The sudden demise of Britain's oldest investment bank ____ global markets.

　　A.vibrated B.swung C.trembled D.jolted

　　9.The tests show the earlier in life a person hears a sound the longer it is ____.

　　A.retained B.preserved C.remained D.reserved

　　10.The researchers test college students ____ to foreign speech before their second birthday but not since.

　　A.disclosed B.exposed C.exhibited D.revealed

　　11.The government has provided the capital library with heavy ____ to keep it one of the largest in the world.

　　A.subscriptions B.tips C.subsidies D.bonuses

　　12.The doctor took his temperature,it was two degrees above ____.

　　A.ordinary B.average C.regular D.normal