虚拟的条件有时通过某些介词短语来表达. 如:We didn’t know you were in trouble at that time,otherwise we would have given you a hand. 我们当时不知道你遇到了困难,要不然我们会帮助你的. 除了otherwise(否则)以外,能够表示虚拟条件的词和短语还包括:but that(要不是)、without(没有)or(不然)、under...circumstances(在……的情况下)、in the past(在过去)等等. He reminded of what I otherwise would have forgotten.