初次应答中首先产生的抗体是（）。
A.IgG
B.IgA
C.IgM
D.IgE
E.IgD
参考答案：C
We lost our way in that small village, otherwise we________ more places of interest yesterday.
A．visited
B．had visited
C．would visit
D．would have visited
()项目通常会有一个被称作工作说明书SOW（StatementOfWork）的范围说明
