Do you know the difference between conditional forms such as “と“, “ば“,“なら“, “たら“?
[to][ba][nara][tara]
“と“ means “when“. It is mainly used to describe natural consequences/results of something or what is supposed to happen when you do something, such as natural phenomena, habits and instructions.
“ば“ means “if...then“. It is mainly used to express a general condition. You can explain what you will do or what will happen if a certain condition is fulfilled.
“なら“ means “if/in the case that“. It is mainly used to express a contextual condition. You can give opinions/suggestions for the topic that someone brings up.
“たら“ means “when/if“. It is used to make conditional sentences for all of the above cases.
“ば“, “なら“ and “たら“ are often used with "もし". If you think the condition of something is certain or likely to happen, you can omit "もし".
It is better to use “たら“ if you don’t know how to use and differentiate them.
“と“, “ば“ and “なら“ are interchangeable with “たら“ depending on the context, but there is a slight nuance.
- Ken: Around that mountain, there is a lot of snow during winter. So we should climb until the beginning of next month.
[OK]八ヶ岳周辺は、冬になると、雪が降る。だから、来月初旬までに登ろうよ。(*1)
[NG]八ヶ岳周辺は、冬になれば、雪が降る。だから、来月初旬までに登ろうよ。
[NG]八ヶ岳周辺は、冬になるなら、雪が降る。だから、来月初旬までに登ろうよ。
[OK]八ヶ岳周辺は、冬になったら、雪が降る。だから、来月初旬までに登ろうよ。(*1)(*1) It indicates natural phenomena.
- Leo: All right. I'd like to book a hotel for 2 nights, from October 24 to 25, if it works for you?
[NG]もしよいと、10月24、25日の二日間、ホテルを予約しようと思うんだけど。
[OK]もしよければ、10月24、25日の二日間、ホテルを予約しようと思うんだけど。(*2)
[NG]もしよいなら、10月24、25日の二日間、ホテルを予約しようと思うんだけど。
[OK]もしよかったら、10月24、25日の二日間、ホテルを予約しようと思うんだけど。(*2)(*2) "もしよければ" is a little more polite than "もしよかったら", but both words can be used in the same situation.
- Ken: That would be great! When it comes to Nagano prefecture, nothing is better than Soba!
[NG]いいね！長野県と言うと、そばでしょう！
[OK]いいね！長野県と言えば、そばでしょう！
(It indicates common sense that Soba in Nagano is famous.)
[OK]いいね！長野県なら、そばでしょう！
(It indicates that Ken recommends Soba.)
[OK]いいね！長野県だったら、そばでしょう！ - Leo: I’ll order it for dinner at the hotel if you want to eat.
[NG](もし)食べたいと、予約するよ。
[OK](もし)食べたければ、予約するよ。(*3)
[OK](もし)食べたいなら、予約するよ。(*3)
[OK](もし)食べたかったら、予約するよ。(*3)(*3) "食べたければ", "食べたいなら" and "食べたかったら" have the same meaning. "食べたければ" is a little more polite than the others, but I feel that "食べたかったら" sounds kind. It depends on the context and your facial expression.
- Ken: Thanks! It’s a deal!
いいね。決まり！
(It indicates common sense or Ken’s suggestion.)