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How to Say ‘I'm really sorry.’ in Japanese

本当にすみませんでした。

hontou ni sumi mase n deshi ta

[hon-TOH nee soo-mee mah-seh n DEH-shee tah]

💬 Usage Tip: すみませんでした is the past form of すみません, so it apologizes for something that already happened rather than just saying "excuse me". 本当に is said (hontō ni).

Phrase Breakdown

本当に

hontou ni

truly / really

本当に (hontou ni) adds strong sincerity. Hold the long 'tou' for two beats.

Example

本当にありがとう。

Thank you so much.

Words in this phrase

本当

hontou

[hon-TOH]

really

Truly or genuinely.

Example

本当にありがとう。

Thank you very much.

に

ni

[nee]

(adverb-forming particle)

Turns 本当 into the adverb 'really, truly'.

Example

本当にありがとう。

Thank you so much.

すみませんでした。

sumi mase n deshi ta

I'm sorry (for what happened)

This is the past form of すみません, used to apologize for something already done. The 'u' in 'su' is light.

Example

遅れてすみませんでした。

I'm sorry for being late.

Words in this phrase

すみ

sumi

[soo-mee]

excuse me; sorry

A polite attention-getter and light apology. Used to call a pharmacist/staff or to be polite before asking for help.

Example

すみません、薬剤師さん。

Excuse me, pharmacist.

ませ

mase

[mah-seh]

polite negative (part of ません)

「ませ」 is part of 「ません」, the polite negative form.

Example

はいていません。

I haven’t vomited.

ん

n

[n]

Negative verb ending

The ending used to make the verb negative in a sentence.

Example

私は行きません。

I am not going.

でし

deshi

[DEH-shee]

was (polite copula stem)

Stem of the polite copula です in its past form, combined with た to make でした.

Example

昨日は雨でした。

It was rainy yesterday.

た

ta

[tah]

past tense ending

This ending completes the polite past tense form.

Example

空席がございまし た。

There were vacant seats.

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