LEARN + JAPANESE / Note 99 JLPT N5

Since, Because (ので)

ので attaches to the plain form and gives a reason, much like から, but softer and less assertive, common when explaining yourself politely or asking permission.

In Real Life
から states a reason as a fact, sometimes bluntly, while ので frames it as a shared, reasonable explanation, which is why it shows up so often right before a polite request like てもいいでしょうか. の-adjectives and nouns take な before ので, just as they do before の itself: 好きなので, 今日なので.
In Real Life
Trailing off after ので, leaving ちょっと。。。 unfinished, is a very natural way to decline an invitation without spelling out a flat no, letting the reason imply the refusal on its own.

Vocabulary

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