We are()receipt()your letter of March 18 offering us the goods()US$ 80 per dozen on the usual terms. A、of⋯of⋯onB、in⋯of⋯atC、in⋯of⋯forD、of⋯of⋯at

We are()receipt()your letter of March 18 offering us the goods()US$ 80 per dozen on the usual terms.

A、of⋯of⋯on

B、in⋯of⋯at

C、in⋯of⋯for

D、of⋯of⋯at


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