teeter on the verge

Translations
балансировать на грани
He teetered on the verge of a breakthrough.
Он балансировал на грани прорыва.
Definitions
To be in a precarious or unstable position, close to a critical point or decision, often implying that a small change could lead to a significant outcome.
Words
teeter

verb
балансировать
on

preposition
на
the

article or possessive pronoun
определённый
verge

noun
грани