不管业务协商是以书面还是口头进行，一旦发盘或还盘被接受，便认为是达成了交易。也就是说，合法的合同既可以是书面的，也可以是口头的。
【正确答案】：No matter whether business negotiation is conducted orally or by way of writing, transaction is considered concluded once an offer or a counter-offer is accepted. That is to say, a legitimate contract can be either in written or oral form.
【题目解析】：参见教材P109。