If you don't go now you won't be able to go for a while
If you don't go to the bathroom now you won't be able to go for a while
これはそのまま「今行かないとしばらく行けなくなるよ」の訳になりますね。ここは「If you don't go now」で「今行かないと」、「won't be able to go」で「行けなくなる」と。「for a while」が「しばらく」となります。
二番目の例は「今トイレに行かないとしばらく行けなくなるよ？」になります。
If you don't go now, you'll have to wait a long time before you can go again.
We commonly use the phrase "to go" as a short way to talk about going to the bathroom. For example: I've got to go really bad! This is particularly common in American English. I hope that this helps! :)
"to go" は "to go to the bathroom"（トイレに行く）を省略した言い方としてよく使われます。
例えば：
I've got to go really bad!（本当にトイレに行かないと）
これは特にアメリカ英語で一般的です。
参考になれば幸いです！ :)
You should probably go now, I don't think you'll be able to go later.
Now's your chance!
Go now or forever hold your peace.
"You should probably go now, I don't think you'll be able to go later." This is a very indirect and gentle way of suggesting to someone that now is the only opportunity they will have to go.
"Now's your chance!" is an English phrase that means that right now is your best opportunity to do something.
"Go now or forever hold your peace." is an older English phrase that means do something now otherwise you won't get to do it forever. It's a more light-hearted way of saying you should do something now rather than later.
"You should probably go now, I don't think you'll be able to go later."（たぶん今行っておいた方がいいよ、この先はないと思うから）
これは、行く機会は今しかないと伝える非常に遠回しで穏やかな言い方です。
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"Now's your chance!" は「今がそれをする最高の機会だ」という意味のフレーズです。
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"Go now or forever hold your peace." は「今それをしなさい、さもないと二度とできなくなる」という意味の古いフレーズです。これは、後からでなく今した方がいいと伝える楽しい言い方です。
Use the restroom now, the next one is not close by!
If you don't use the bathroom now, there isn't another for a while!
Both these sentences mean that you will have to wait a while before we get to another restroom for you to go.
"Use the restroom now, the next one is not close by!"
"If you don't use the bathroom now, there isn't another for a while!"
どちらの文も「これからしばらくトイレに行くことができない」という意味です。
"Use the restroom now, the next one is not close by!"（今のうちにトイレに行っておきなさい。この先は近くにはないから）
"If you don't use the bathroom now, there isn't another for a while!"（この先はしばらくトイレはないよ）
When talking to kids it is important that they understand the consequences of their actions, such as not using the bathroom. You don't want to drive 30 minutes and have her suddenly have to go! This is your last chance to go to the bathroom and there won't be another bathroom for awhile are both good ways to let her know that this is the last time she can go the bathroom for awhile.
You won't be able to go for a while if you don't go now
If you don't go to the bathroom now you won't be able to for a while
If you want to explain that someone should do something as it might be a little while until they can do it again
'you won't be able to go for a while' explains this but to say 'if you don't go to the bathroom now you won't be able to for a while' explains it in more detail
「しばらく～できないから、今のうちにしておいた方がいい」と説明したいなら、'you won't be able to go for a while'（しばらく行けない）と言えます。
'if you don't go to the bathroom now you won't be able to for a while'（今トイレに行かないと、しばらく行けない）はより具体的な言い方です。
If you don't go now, you won't be able to go for a while.
This is your last chance to go for a while.
"If you don't go now, you won't be able to go for a while." is an easy way to say that if you don't go to the bathroom now, you won't have another chance (be able to) for a while.
The use of the phrase 'able to' means that there won't be the opportunity in the case.
Perhaps a more clear way to say this is "This is your last chance to go for a while.", which uses the word 'chance' as an opportunity to choose to do something rather than the ability to do something or not, which can be clearer.
"If you don't go now, you won't be able to go for a while."（今行かないとしばらく行けないよ）は、「今トイレに行かないと、しばらく行けない」のシンプルな言い方です。
'able to' は、機会がないことを表します。
"This is your last chance to go for a while."（これを逃したらしばらく行けないよ）、これはより明確かもしれません。'chance' を使って「能力」ではなく「機会」について言っています。
Better go to the toilet now as it'll be a long time before you get another chance!
Best use the loo now if you want as it's a long trip with few stops
You are going to be driving for a while and there will be no place to go to the restroom for a while. To your daughter, you want to tell her that she won't be able to go for a while if she doesn't go now.
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