FIDIC合同条件下,签发( )必须由工程师亲自处理。
A.付款证书
B.工程接收证书
C.工程计量
D.履约证书
E.开工令
参考答案:A,B,D,E
Most of the teachers ______ to visit our school were young ones.
A.invited
B.to invite
C.being invited
D.had been invited
磁性次晶格