Our offer is firm （）five days and we expect to hear from you at early date.

We offer firm CIF, Lagos shipment()30 days, subject to your reply here ()10 a.m., our time.

A、within,within

B、for,by

C、during,by

D、in,untill

A、for

B、on

C、of

D、in

We trust that you will be able to accept our offer, which shal() against reply by cable

A、kept open

B、keep valid

C、be kept firm

D、be keeping open

We trust that you will be able to accept our offer, which shall() against reply by cable

A、kept open

B、keep valid

C、be kept firm

D、be keeping open

A．A.are firm offers

B．B.are firm offer

C．C.is firm offer

D．D.is a firm offer

A．On average

B．At best

C．In return

D．After all