Learn Hardcore Japanese: sudeni meeru ha okutta kara, mou henkou ha sinai. - I’ve already sent the email, so I won’t make any more changes.

は marks the topic and often adds a contrastive nuance.
メールは送った means “as for the email, (I) sent it,” highlighting “email” as the point at issue (possibly contrasting with something not sent).
もう変更はしない means “as for changes, (I) won’t do (any),” focusing specifically on “changes” as the thing being denied.

Why is there no を (object marker) in メールは送った and 変更はしない?

When a noun that would normally take を is made the topic, は replaces を: メールを送った → メールは送った; 変更をしない → 変更はしない.
The underlying grammar is the same; marking the noun with は shifts the focus to it (often contrastively).

Why is は pronounced “wa” here?

The topic particle は is always pronounced “wa,” not “ha.” This is a historical spelling convention.
You’ll also hear it in greetings like こんにちは and こんばんは, where the final は is the topic particle pronounced “wa.”

Are すでに and もう redundant? Why use both?

No redundancy here—they’re doing different jobs:
- すでに (“already”) states a completed fact in the first clause: すでにメールは送った.
- もう with a negative means “no longer/any more”: もう変更はしない.
すでに sounds a bit more formal/written than もう, but using both like this is natural.

Can I swap すでに and もう?

Yes, depending on nuance:
- もうメールは送ったから、変更はしない. (colloquial)
- メールはすでに送ったから、もう変更はしない. (keeps すでに for the “already” and もう for the negative)
Using もう in both places is possible but can feel repetitive: もうメールは送ったから、もう変更しない.

Does から mean “because” or “after” here?

Here it means “because”: 送ったから = “because (I) sent (it).”
“After doing” is Vてから: 送ってから = “after sending.” Different grammar and meaning.
- Example: 送ってから、確認します = “After sending, I’ll check.”

Why is the first clause past (送った) but the second is non-past negative (しない)?

送った is past/perfective: the sending is completed.
しない (non-past) is used for future intention/decision in Japanese: “(I) will not (make changes).”
Mixed tenses like this are normal: a past reason leading to a future decision.

What’s the difference between 変更はしない, 変更しない, 変更はできない, and 変更がない?

変更はしない: “As for changes, (I) won’t do (any).” Contrastive; focuses on “changes” as the excluded action.
変更しない: Plain “won’t change/make changes,” without extra contrast.
変更はできない: “(I) can’t make changes.” This is inability/impossibility, not choice.
変更がない: “There are no changes.” Describes the situation, not an action/decision.

Could I say メールを送った or メールした instead of メールは送った?

メールを送った: Neutral, plain statement “(I) sent an email.”
メールは送った: Topical/contrastive “As for the email, (I) sent it” (e.g., implying something else wasn’t done).
メールした: Colloquial “(I) emailed.” Very common in speech.
送信した: More formal/technical (“transmitted/sent”).

How would I say this politely?

Can I add sentence-ending particles like よ or ね?

Yes, to adjust tone:
- もう変更はしないよ. (assertive, informing)
- もう変更はしないね. (seeking agreement/confirmation)
- もう変更はしないよね. (assertive + checking understanding)
Without them is neutral.

Is the word order flexible?

Yes. Examples:
- メールはすでに送ったから、もう変更はしない.
- すでにメールは送ったから、変更はもうしない.
- もう変更はしない。メールはすでに送ったから。 (split into two sentences for emphasis)
Adverbs like すでに/もう can appear before the topic or after it; nuance shifts slightly toward what you foreground.

Who is the subject here? There’s no “I.”

Japanese often omits subjects when they’re clear from context. Here it’s most likely “I” (or “we”) in a typical conversation.
You can make it explicit if needed: 私はすでにメールを送ったから、もう変更はしません.

Can I use だから instead of から?

Not as 送っただから (that’s ungrammatical).
You can split it into two sentences: すでにメールは送った。だから、もう変更はしない. This is natural and a bit emphatic.

Is it okay to write spaces like in the example?

In normal Japanese, you don’t put spaces between words. A standard written form would be:
- すでにメールは送ったから、もう変更はしない。
すでに is often written in kanji as 既に.

Could I say 送ってある or 送ってしまった instead of 送った?

メールはもう送ってある: “The email has (already) been sent (and is in a state of ‘done’ for a purpose).” Emphasizes the resulting state that benefits the current situation.
送ってしまった: Completion with a nuance of finality or (sometimes) regret/accident: “(I’ve) already sent it (so, alas, changes aren’t possible).”
Choose based on nuance; 送った is the neutral past/perfective.