to be on the verge; to be on the brink; to get close
大雨で川が氾濫に成り掛けている。
The river is on the verge of flooding due to heavy rain.
試合に負け成り掛けたが最後に逆転した。
We were on the verge of losing the match but made a comeback at the end.
会社が倒産に成り掛けるほどの窮地に立たされた。
The company was driven into a predicament so severe it was on the brink of bankruptcy.