Welsh has no words for "yes" or "no"

"Welsh has no word for yes or no" always seems a bit strange to me. Because yes there's no one single Welsh word that is used for "yes" or "no" that directly translates to all the English uses of "yes"/"no". But the Welsh words we use instead still mean "yes" or "no". They would still translate to "yes" or "no" in English.

Like, "ydw" as an answer literally means "I am" but that means "yes" essentially, yes? Like you'd still translate it to "yes" if you were translating a Welsh text to English.

• "Wyt ti'n mynd?" "Ydw, dwi'n mynd" -> original Welsh
• "Are you going?" "I am, I'm going" -> more literal translation 
• "Are you going?" "Yes, I'm going" -> translation that keeps the tone/feel the same between the two languages

The "I am" in the English translation sounds more emphatic like "yes, I definitely am going!" whereas it doesn't sound emphatic in the Welsh. Like it just translates to "yes" in this context.