Question

Look at what they can do without legs that animals with legs

Answer 1

（主语应该是你或你们 这是祈使句）Look at（谓语） what（宾语） they can do without legs that （what的定语）animals with legs can't do.

they can do without legs 是what引导的宾语从句

that animals with legs can't do.that引导的从句做what的定语