teeter

The pile of books teetered and fell to the floor.那一摞书摇摇晃晃的，全都倒在了地板上。

She teetered down the street in her high heels.她穿着高跟鞋深一脚浅一脚地走在大街上。

Our relationship teeters between friendship and romance.我们的关系在友情和爱情之间摇摆。

The bird is teetering on the edge of extinction. [=the bird is almost extinct]那种鸟濒临灭绝。

The countries are teetering on the brink of war. [=the countries are close to going to war]这些国家处于战争的边缘。