When to use て forms with commas?


Consider two variants of a sentence with a comma:

  1. 雨が **降って** 、傘を持ってきてよかった。
  2. 雨が **降った** 、傘を持ってきてよかった。

I've seen that (2) is grammatical in Japanese (as opposed to English, where it
would be considered a "run-on" sentence). Do both variants mean the same thing
("It was raining, so I was glad I bought my umbrella")? If not, what is the
difference between them, and in general when should one use the て-form with
commas?

My guess is that (1) has more of a cause and effect relationship ("It was
raining, and _then_ , because of that, I brought an umbrella and was glad").
Then I suppose (2) is more disjointed, and could mean ("It was raining, and I
happened to have an umbrella, so I was glad")?




Which is the intended meaning of your Sentence (1)?

  * **A** : It was actually raining when I went out, so I took an umbrella. It ended up being useful in some other way (say, as a photography reflector or a weapon).
  * **B** : I brought an umbrella when I went out because I anticipated that it might rain. It did end up raining, so the umbrella was indeed useful.

If **A** is the intended meaning, your Sentence (1) is correct. If **B** is
the intended meaning, Sentence (1) is awfully unnatural because of the
limitation described in the last part of [this article](https://www.learn-
japanese-adventure.com/te-form-cause-reason.html).

> In this sentence pattern, Sentence 1 and Sentence 2 are sequential events.
> In other words, Sentence 1 takes place first and Sentence 2 takes place
> after that.
>
>   1. 明日試験があって、今日準備しなければなりません。 X
>

Therefore, when you say 雨が降っ **て** 傘を持ってき **て** よかった, "雨が降った" → "傘を持ってきた" →
"よかった" must happen in this sequence. **A** satisfies this, but **B** doesn't.
If **B** is what you mean, you must say "(本当に)雨が降った **ので**
、(あらかじめ)傘を持ってきてよかった".

* * *

As for Sentence (2), it's just two independent sentences somehow joined with a
comma instead of a period. While such a technique may be deliberately employed
to convey halting thoughts in monologues or similar contexts, it's simply
incorrect as standard Japanese.




Which is the intended meaning of your Sentence (1)?

  * **A** : It was actually raining when I went out, so I took an umbrella. It ended up being useful in some other way (say, as a photography reflector or a weapon).
  * **B** : I brought an umbrella when I went out because I anticipated that it might rain. It did end up raining, so the umbrella was indeed useful.

If **A** is the intended meaning, your Sentence (1) is correct. If **B** is
the intended meaning, Sentence (1) is awfully unnatural because of the
limitation described in the last part of [this article](https://www.learn-
japanese-adventure.com/te-form-cause-reason.html).

> In this sentence pattern, Sentence 1 and Sentence 2 are sequential events.
> In other words, Sentence 1 takes place first and Sentence 2 takes place
> after that.
>
>   1. 明日試験があって、今日準備しなければなりません。 X
>

Therefore, when you say 雨が降っ **て** 傘を持ってき **て** よかった, "雨が降った" → "傘を持ってきた" →
"よかった" must happen in this sequence. **A** satisfies this, but **B** doesn't.
If **B** is what you mean, you must say "(本当に)雨が降った **ので**
、(あらかじめ)傘を持ってきてよかった".

* * *

As for Sentence (2), it's just two independent sentences somehow joined with a
comma instead of a period. While such a technique may be deliberately employed
to convey halting thoughts in monologues or similar contexts, it's simply
incorrect as standard Japanese.

