愚かな行為をしたのかもしれないと思い始めた。

foolish; stupid

act; deed; conduct

indicates direct object of action; indicates subject of causative expression; indicates an area traversed; indicates time (period) over which action takes place; indicates point of departure or separation of action; indicates object of desire, like, hate, etc.

to do; to cause to become; to make (into); to turn (into); to serve as; to act as; to work as; to wear (clothes, a facial expression, etc.); to judge as being; to view as being; to think of as; to treat as; to use as; to decide on; to choose; to be sensed (of a smell, noise, etc.); to be (in a state, condition, etc.); to be worth; to cost; to pass (of time); to elapse; verbalizing suffix (applies to nouns noted in this dictionary with the part of speech "vs"); creates a humble verb (after a noun prefixed with "o" or "go"); to be just about to; to be just starting to; to try to; to attempt to

indicates possessive; nominalizes verbs and adjectives; substitutes for "ga" in subordinate phrases; (at sentence-end, falling tone) indicates a confident conclusion; (at sentence-end) indicates emotional emphasis; (at sentence-end, rising tone) indicates question

may; might; perhaps; may be; possibly

to become known; to come to light; to be discovered; to be known; to be understood; to obviously not amount to much; to seem trivial; to be evident; to be obvious; to go without saying; to be very intense (worry, hope, etc.); to be extremely severe

if; when; and; with; particle used for quoting (with speech, thoughts, etc.); quoting particle; promoted pawn; indicates question (sentence end)

to think; to consider; to believe; to think (of doing); to plan (to do); to judge; to assess; to regard; to imagine; to suppose; to dream; to expect; to look forward to; to feel; to desire; to want; to recall; to remember