QUES: As we have already mentioned it consists of two volumes and these are divided into an introduction ten chapters and various appendices

correct the punctuation.

CORRECTED: As we have already mentioned it consists of two volumes, and these are divided into an introduction, ten chapters, and various appendices.

QUES: If you wish to pay with a Gift Voucher enter card number here

correct the punctuation.

CORRECTED: If you wish to pay with a Gift Voucher, enter card number here

QUES: In addition to offer you a calendar insert on your pages it will be possible to display in your widget bar

correct the punctuation.

CORRECTED:
In addition to offer you a calendar insert on your pages, it will be possible to display in your widget bar.