We regret ______ to accept your terms of payment and therefore have to return the order to you.

We are glad to receive your telegraphic order of May 6, ______ regret that we can not supply the goods ______ the end of May.

Ifwehadbeeninformedintime,we____themforyou.

The consignment certainly does not match the samples ____ you sent us last month.

Webelievesuchanagreementwillprove____.