Many Japanese verbs are formed by combining Chinese-derived nouns and a verb する. Virtually all of those with nouns with MORE THAN ONE Chinese characters can be used either する or をする. Please see the examples below:
- 私は混乱(を)した -> I got confused
- 誤解(を)しないで下さい -> Please don’t get me wrong
- 外がうるさくて集中(を)するのが難しい -> It’s hard to focus because it’s very noisy outside
There are a few exceptions, basically for the ease of uttering:
- 彼は私の言った事を誤解した -> He misunderstood what I said
- 彼は私の言った事を
誤解をした-> This is not grammatically wrong, but a close repetition of を is simply mouthful, thus will be avoided
However the same does not apply to the verbs with ONE Chinese character
For instance the followings are examples of する verbs that cannot have を inserted
- 愛する, 害する, 関する, 察する, 接する, 属する, 対する, 達する, 脱する, 適する, 徹する, 熱する, 罰する, 反する
Meanwhile others like 得(を)する, 損(を)する can go either way.
In this website, the ones that cannot have を are shown as one word as below;
And the ones that can go with or without を are show as below:
