英语语法分析

Tunas, mackerels, and billfishes have even more sophisticated adaptations than these to improve their hydrodynamics.

金枪鱼、鲭鱼和长嘴鱼有比这些更复杂的适应性，以提高自己的流体动力学。

Although most of their scales have been lost, tunas and mackerels retain a patch of coarse scales near the head called the corselet.

虽然它们的大部分鳞片已经消失，但金枪鱼和鲭鱼头部附近仍保留着一块粗糙的鳞片，称为胸甲。

You should catch at least two mackerels.

你至少得钓两条青鱼。