invertebrate|invertebrates

蜗牛是一种没有脊椎的无脊椎动物。

A snail is an ___invertebrate that lacks a backbone.

蝴蝶和蜘蛛都是无脊椎动物。

Butterflies and spiders are both ___invertebrates.

她不愿意为自己的观点辩护，真是个软骨头！

She refused to stand up for her opinions - what an ___invertebrate!