よ
yo
Putting it in their hand: よ
The picture You hold something the other person doesn't have and push it across to them. A gentle push is a kindness; a hard shove is shoving it in their face. よ pushes across something the other person doesn't have; ね rolls a ball about something you both already have.
Where the picture shows up in よ
-
passing over what they missed
財布、落ちましたよ。
saifu, ochimashita yo
Excuse me — you dropped your wallet.
Picking up a dropped wallet behind someone who is walking on, and holding it out at their back.
The opposite of ね: use よ only when you assume they don't already know.
-
passing over your intention
私がやりますよ。
watashi ga yarimasu yo
I'll do it, leave it to me.
Sliding your hands under a load someone is struggling with and taking its weight onto your side.
-
passing over your certainty
大丈夫ですよ。
daijoubu desu yo
It's fine, honestly — don't worry.
A hand laid on the shoulder of someone who is anxious, leaning a little weight into it.
-
the hard shove
早くしてよ。
hayaku shite yo
Come on, hurry up.
A flat palm pushing at someone's back to hurry them along.
The same よ turns rude when pushed hard. Saying 違いますよ to a senior sounds like you're lecturing them.
All of it in one picture
It is one picture: something moves from your hand into theirs. Pick up the dropped wallet and hold it out, and you are passing over a fact they didn't have; take the load off them, and you are passing over your intention. Lay a hand on a worried shoulder and you are passing over your certainty; push at their back and the same hand has simply got harder, which is why it nags. So what colours よ isn't what you pass over, but how hard you push.