All trains と言うと「すべての電車」「どの電車も」と言うニュアンスになります。
また It doesn't matter which train you take は「どの電車でもいいですよ」という意味の言い方です。
It doesn't matter で「関係ない」という意味の表現なので「どの電車に乗っても関係ない（関係なくつけるよ）」になります。
You are walking along platform three waiting for you train home after work. A foreignh tourist approaches you and asks:
"Excuse me, which train do I take to get to Exeter, please?" You explain:
"Well, the next station is Exeter and Exeter is an important station, so every train stops at Exeter. So, just take the first train - anytime!"
"Thank you very much!"
あなたは仕事を終えて家に帰る汽車を待ちながらプラットフォーム３に沿って歩いています。
外国人の観光客があなたに近づいてきて尋ねます：
"Excuse me, which train do I take to get to Exeter, please?"
ーすみません、どの汽車がExeterへ向かいますか？
説明します：
"Well, the next station is Exeter and Exeter is an important station, so every train stops at Exeter.
So, just take the first train - anytime!"
ー次の駅はExeterで、Exeterは大きな駅なので、すべての汽車がExeterでとまります。
だから、早い汽車に乗ったらいいですよ！いつでも！
"Thank you very much!"
ーありがとう！
You can get on any train since they are all headed to Station A.
You can take any train because all of them stop at that station.
▢ All trains stop at Station A.
全ての電車は = All trains
A駅 = Station A
に行きます = go to / pass through / stop at
▢ You can get on any train since they are all headed to Station A.
headed to Station A = A駅に行きます
▢ You can take any train because all of them stop at that station.
all of them = 全ての電車
stop at that station = その駅で止まる
▢ All trains stop at Station A.
全ての電車は = All trains
A駅 = Station A
に行きます = go to / pass through / stop at
▢ You can get on any train since they are all headed to Station A.
headed to Station A = A駅に行きます
▢ You can take any train because all of them stop at that station.
all of them = 全ての電車
stop at that station = その駅で止まる
Get on any train, as all of them will take you to (A) station.
Get on the next train, as all trains travel through (A) station.
The answer needs two parts. You need to tell them to get on any train or the next train.
But you need to explain why so that they are reassured that they are getting on the right one.
And this information will help them in the future if they need to get to the (A) station.
If you just gave them the first part
- get on the next/any train, they will not understand the full reason why.
You can take any train, as they all pass through A station
For a simple way of telling someone that all/every train passes through A station then you could say
'Every train passes through A station' or 'All the train passes through A station'
To explain a little better/clearer that they can get any train to A station the you could say
'You can take any train, as they all pass through A station'
全ての電車がA駅を通過することをシンプルに伝えるならば、以下のフレーズが使えます。
'Every train passes through A station'（全ての電車がA駅を通ります）
'All the train passes through A station'（全ての電車がA駅を通ります）
どの電車に乗ってもA駅に行けることをより明確に伝えるなら、以下のフレーズが使えます。
'You can take any train, as they all pass through A station'（全ての電車がA駅を通るので、どの電車に乗っても大丈夫です。）
You can get on any of the trains. All of them pass through where you want to go.
All of the trains pass through where you want to get off. You can take any of the trains.
When you want to explain to someone that all the trains pass through a certain station, so getting in on any train is fine; then you may say it in the following ways:
-You can get on any of the trains. All of them pass through where you want to go.
-All of the trains pass through where you want to get off. You can take any of the trains.
-All trains stop at that station.
特定の駅について、すべての電車がそこを通るのでどの電車に乗っても大丈夫だと伝える言い方です：
-You can get on any of the trains. All of them pass through where you want to go.
どの電車に乗っても大丈夫だよ。全て、あなたの行きたいところを通るから。
-All of the trains pass through where you want to get off. You can take any of the trains.
どの電車もあなたの降りたいところを通るから、どれに乗っても大丈夫だよ。
-All trains stop at that station.
どの電車もその駅で止まりますよ。
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