When the seller receives the buyer’s counter-offer, and he finds some terms and conditions unacceptable to him, he will state his own opinions in a letter, which is called as _____。

Please see to it that the goods we ordered are shipped as soon as the covering letter of credit ______ you.

Please____usyourcompetitivepriceforthefollowingitems.

Anorderisarequesttosupplyaspecifiedquantityofgoods,whichmayresultfrom________or_________withsubsequentquotations.

Whenthesellerreceivesthebuyer’scounter-offer,andhefindssometermsandconditionsunacceptabletohim,hewillstatehisownopinionsinaletter,whichiscalledas_____。