* 難しい (muzukashii): This is the most common and versatile word for "difficult." It can refer to tasks, concepts, people, situations, etc. This is generally a good default choice.
* 大変 (taihen): This word means "difficult," but it often implies a lot of trouble, hardship, or effort. It emphasizes the magnitude of the difficulty rather than the inherent complexity. It can also mean "terrible" or "awful" depending on context.
* 困難 (konnan): This word is more formal and emphasizes the obstacles or challenges involved. It's often used in more serious or official contexts.
* 厄介 (yakkai): This word means "troublesome" or "awkward." It implies something difficult to handle or deal with because it's inconvenient or problematic.
To choose the best word, consider:
* What is difficult? A task? A concept? A person? A situation?
* How difficult is it? Is it mildly challenging or extremely hard?
* What aspect of the difficulty is being emphasized? The complexity? The effort required? The inconvenience? The obstacles?
For example:
* "The exam was difficult." → 試験は難しいでした。(Shiken wa muzukashii deshita.)
* "It's been a difficult year." → 今年は大変でした。(Kotoshi wa taihen deshita.)
* "The negotiations were difficult." → 交渉は困難でした。(Koushō wa konnan deshita.)
* "Dealing with him is difficult." → 彼と付き合うのは厄介だ。(Kare to tsukiauu no wa yakkai da.)
Therefore, while `難しい (muzukashii)` is a good starting point, consider the context to choose the most accurate and nuanced translation.