【C10】A．have broughtB．have been broughtC．have takenD．have been taken

【C10】______A．had votedB．had been votingC．have votedD．were voting

【B16】A．to having foundB．to have been foundC．to have foundD．to find

A．Gases have been heated to a temperature of multimillion－degree.B．Gases have been dra

【C17】A．must have beenB．may have beenC．could have beenD．should have been

【C8】A．have keptB．had keptC．have been keepingD．had been keeping

【C10】A．useB．have usedC．usedD．are used