呢句係點解?

A is the seller.

B is the buyer.

There is no agent.

B Ltd entered into a contract with A Ltd => B與A簽約
(B簽約以確定) to purchase VGA cards for A => 幫A買VGA cards
如果係 from A，A就係賣方，即由（from）A度買野
但呢句係 for A，為 A 買野，即幫 A 買野，所以 B 係 agent；A 係買方。

2007-05-24 16:31:55 補充：
完全錯誤
希望問者信左冇出事

i think A is the buyer and B is the angent.