但由一个主句和一个甚至几个从句组成 的复合句则因为层次较多、结构复杂而 理解比较困难。在这种情况下,要先找 到主句并弄清主句中的主、谓语以及说 明和修饰主、谓语的那些成份,然后在 从句中找出引导词 a previous study(palm et al. 1998 has indicated that most parasite species of the Antarctic fish, Notothenia coriiceps, appear to be broadly distributed within antarctic waters. which would correspond to a low host specificity in higher latitudes但由一个主句和一个甚至几个从句组成 的复合句则因为层次较多、结构复杂而 理解比较困难。在这种情况下，要先找 到主句并弄清主句中的主、谓语以及说 明和修饰主、谓语的那些成份，然后在 从句中找出引导词 A previous study (Palm et al. 1998) has indicated that most parasite species of the Antarctic fish, Notothenia coriiceps, appear to be broadly distributed within Antarctic waters, which would correspond to a low host specificity in higher latitudes