听句子，缩写原文。（）

A．We cannot reach an agreement, let alone a spoken promise.

B．We’d better draft and then sign a written agreement.

C．We generally keep our promises in business transactions.

D．We hope you understand why we are unable to keep our promises.

施工期的起始日是( )。

A．合同内约定的开工日

B．合同签字日

C．“开工令”中指的应开工日

D．双方协商确定