Breakdown of tyuui wo sinai to, saihu wo ototosite simaimasu.
をwo
direct object particle
とto
conditional particle
〜て〜te
connective form
〜ない〜nai
negative form
財布saihu
wallet
注意するtyuuisuru
to pay attention
注意tyuui
attention
落すotosu
to drop
しまうsimau
to end up (regretfully)
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Questions & Answers about tyuui wo sinai to, saihu wo ototosite simaimasu.
In the phrase 注意をしないと, what does the construction ~しないと mean?
The pattern ~しないと is a casual conditional meaning “if you don’t (do ~)”. Here, 注意をしないと means “if you don’t pay attention.”
Why is 注意 followed by を and しない? Isn’t 注意 a noun?
Yes, 注意 is a noun meaning “attention” or “caution.” To turn it into a verb phrase, Japanese uses をする:
• 注意をする = “to pay attention”
In the negative, 注意をしない = “not pay attention.”
What role does the particle と play after 注意をしない?
The particle と marks a conditional meaning “if/when.” So 注意をしないと = “if you don’t pay attention.”
Why is the verb in the second clause 落としてしまいます instead of simply 落とします?
The auxiliary ~てしまう adds nuance of regret or unintended result.
• 落とします = “drop” (neutral)
• 落としてしまいます = “end up dropping” or “drop regrettably”
It shows the speaker sees dropping the wallet as an unfortunate accident.
Why is the progressive/te-form 落として used before しまいます?
To attach the auxiliary しまう, you need the te-form of the main verb.
• 落とす → te-form 落として → plus しまいます yields 落としてしまいます.
Could this sentence be made more casual? How?
Yes.
• Drop the polite ~ます: 落としちゃう instead of 落としてしまいます.
• You might also omit some particles: 注意しないと財布落としちゃうよ。
This sounds more conversational and less formal.