它们通常很胆小，极少远离自己的洞穴。

Normally timid, they rarely stray far from their burrows.

《柯林斯英汉双解大词典》

它们通常比便服更舒适、更耐穿。

They are often more comfortable and more durable than civilian clothes.

youdao

它们通常大概每十年出现一次。

They typically appear about once in a decade.

youdao

There's not actually chemical covalent bonds that are formed but it's a non-covalent interaction, usually dominated by hydrogen bonding.

所以配体和受体之间不生成共价键,这是一种非共价化合反应,它们通常以氢键相联

耶鲁公开课 - 生物医学工程探索课程节选

They're just antigens that belong to you and so you don't normally mount an immune response to antigens that are part of you.

它们是你的自身抗原,但通常对自身抗原不会产生免疫反应

耶鲁公开课 - 生物医学工程探索课程节选

Things in dreams were often not what they seemed to be but rather symbols for other things.

梦境中的事物往往并不像,它们看上去那样的简单,它们通常是其他事物的象征。

耶鲁公开课 - 心理学导论课程节选