一、下面每句都有一个标点符号错误，该用标点处未用标点或标点符号用错，改正错误或补写标点。

1.Surely it was them who left the package last night.

2.Our age,as we all know,is a information age.

3.The contract,which stipulations have been negotiated over the past six months,is to be signed again.

4.This letter is accompanied by a questionnaire and a self-addressed envelope.

5.Writing for Business Week,the TV networks were commended by the editor for their coverage of economics.

答：1.them→they 

2.a→an 

3.which→whose或which stipulations of which

4.by→with 

5.the TV networks were commended by the editor→the editor commended in the TV networks