Definition: to watch someone or something carefully Level: B2
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.
