【C13】A．performingB．workingC．operatingD．managing

A．actingB．workingC．malfunctioningD．functioning

The President made a brief visit to Beijing.A．shortB．workingC．formalD．secret

The President made a brief visit to Beijing.A．shortB．workingC．formalD．secret

____________ 查看材料A.dealingB.workingC.smokingD.shopp

【C11】A．then workedB．now workingC．then workingD．who working

We found him（)in the laboratory.A. workB. workingC. to work