observe|observes|observed|observing

科学家观察并描述自然现象。

Scientists ___observe and describe natural phenomena.

研究人员在森林里待了数月，观察气候变化的影响。

Researchers spent months in the forest, ___observing the effects of climate change.

幼儿通过观察周围的人学到很多东西。

Young children learn a lot by ___observing the people around them.

杰克注意到他哥哥脸上焦虑的表情。

Jack ___observed a look of anxiety on his brother's face.

警卫没有注意到谁交付了包裹。

The guards failed to ___observe who delivered the package.

在社会群体之间可以观察到言语风格的差异。

Differences in speech styles can be ___observed between social groups.

她每年夏天观察野生黑猩猩的行为。

She ___observes the behavior of chimpanzees in the wild every summer.