许多动植物物种只存在于雨林中。

Many plant and animal species ___are ___found only in the rainforests.

维生素C存在于柑橘类水果中。

Vitamin C ___is ___found in citrus fruit.

例如考拉熊，不久前在澳大利亚几乎到处都能找到。

An example might be the koala bear, which could ___be ___found almost everywhere in Australia not so long ago.