Learn Hardcore Japanese: eki ni tuitara, kanarazu watasi ni renrakusite kudasai. - When you arrive at the station, be sure to contact me.

With the verb 着く (to arrive), the destination takes に. で marks the place where an action happens; arrival is not an action performed at the station but reaching it, so で is wrong here. へ marks direction and can appear with motion verbs, but with 着く, に is the normal, most natural choice. Examples: 東京に着く, not 東京で着く; 東京へ着く sounds literary/old-fashioned to many ears.

Why does 着いたら use the past form even though it refers to the future?

The たら conditional uses the past plain form to mean “once/when X has happened, then Y.” It marks the condition as becoming true at that future moment. Example: 雨が降ったら、出かけません (If/When it rains, I won’t go out).

Could I use 時 instead of たら here?

Yes. 駅に着いた時、私に連絡してください is also natural. Subtly, 〜たら often feels more like a trigger “once it happens, then do Y,” while 〜時 frames it as “at the time when.” Both work here. Note: 駅に着く時 would mean “when you are about to arrive/before you arrive,” which doesn’t match the intended timing.

What’s the difference between たら, と, ば, and なら in this kind of sentence?

たら: best for “when/once X happens, do Y,” especially with requests. Natural here.
と: implies automatic, inevitable results; it doesn’t go well with requests/commands. Avoid it here.
ば: more hypothetical (“if”); 駅に着けば、連絡してください feels less natural than たら.
なら: topic-based “if it’s the case that…,” not a temporal trigger. Not ideal for this instruction.

What nuance does 必ず add? Is it strong?

必ず means “without fail/definitely.” It is strong—like an insistence. With ください, it’s softened, but it can still sound firm. To soften more: 必ず + ね, or use ご連絡ください/お願いします. Example: 必ずご連絡くださいね.

Why 私に and not 私を or 私へ? Can I omit 私?

With 連絡する, the recipient is marked with に (or へ in more formal/written style). 私を連絡する is ungrammatical. If context makes it obvious, you can omit 私: 駅に着いたら、連絡してください. You can also say こちらに in formal contexts.

How do particles work with 連絡する? What about 連絡をください and 連絡ください?

連絡する is a する-verb; you can say 私に連絡する/してください.
The nominal form 連絡をする is also common: 私に連絡をしてください.
Requests: 連絡をください and the clipped 連絡ください are both widely used. The person still takes に: 私に連絡ください.

Is 連絡してください different from 連絡して?

Yes. 連絡してください is a polite request. 連絡して is casual (friends, equals). You can soften casual further with ね: 連絡してね.

Could I say 連絡します instead?

連絡します means “I will contact (you),” not a request to someone else. To tell them to contact you, use 連絡してください (or a casual/polite variant).

How can I make the sentence more formal or softer?

More formal: 駅に着きましたら、必ずご連絡ください.
Very polite: 駅に着きましたら、必ずご連絡いただけますか / ご連絡願います.
Softer casual: 駅に着いたら、私に連絡してね / 連絡してくれる？.

Can I move 必ず or 私に around?

Yes. Adverbs are flexible:

駅に着いたら、必ず私に連絡してください (default).
駅に着いたら、私に必ず連絡してください (emphasis on “to me”).
In speech, even 駅に着いたら、連絡してください。必ず。 for extra emphasis.

What’s the difference between 着いたら and 着いてから?

Both give the right timing. 〜てから explicitly means “after doing X, then do Y,” emphasizing sequence: 駅に着いてから、私に連絡してください. 〜たら also indicates “once X happens,” with a slight conditional feel. Either is fine here.

Why not use 来たら (as in 駅に来たら)? Is that wrong?

駅に来たら、連絡してください is grammatical but implies “when you come to the station (toward where I am).” 着く focuses on arriving after a journey and is the idiomatic verb with places: 駅に着いたら is the natural choice.

Can I use 着く時 or 着いた時?

着いた時: fine—nearly the same timing as 着いたら. Example: 駅に着いた時、連絡してください.
着く時: means “when you are about to arrive/before arriving,” so it suggests contacting ahead of arrival; that’s a different instruction.

Why do people say ご連絡ください? What is ご?

ご is an honorific prefix for Sino-Japanese nouns. ご連絡ください is a standard polite set phrase meaning “please contact (me/us).” Business/official style often prefers ご連絡 over plain 連絡.

How do I specify the method of contact?

Add the method:

電話で連絡してください (by phone)
メールしてください (email me)
LINEして / メッセージしてください (send a message) Or replace 連絡: 電話してください.

Should ください be written as kana or 下さい?

For the request auxiliary, write ください (kana) in modern standard style: 連絡してください. The kanji 下さい is typically reserved for the independent verb “please give me” (e.g., 水を下さい), though many writers still use kana for both.

Can I drop particles in casual speech?

Yes, in casual conversation: 駅着いたら連絡して (dropping に and 私に) is common and natural among friends. Keep particles in formal speech and writing.

How do I read the key words?

駅 (えき, eki)
着く / 着いたら (つく / ついたら, tsuku / tsuitara)
必ず (かならず, kanarazu)
私 (わたし, watashi)
連絡 (れんらく, renraku)
ください (kudasai)