A four-character idiom meaning many events and many difficulties; a situation full of troubles and hardships.
新しいプロジェクトは多事多難で、予想以上に手間がかかっている。
The new project has been beset with many problems and difficulties and is taking more effort than expected.
今年は会社にとって多事多難の年だった。
This year was a year of many troubles for the company.