hūdan and yahūd

[Mushu]

Peace all,

I was thinking that yahd was the plural form of hdan. I'm not sure on this, but I believe the prefix ?ya? is used to construct broken plural forms, such as in 39/21 ? yanba (springs).

Anyway, I thought I was on to something until I hit 3/67

3/67 Not was Ibrahim yahdiyyan and not narniyyan

I think the irregular endings are due to both nouns being accusative from the transitive kna. But if yahd really is a plural form and not a proper noun, why is it being used here? I would have expected hdan to be used instead, like in 2/111.

Any thoughts? Are there other examples of a plural being used on a singular subject, similar to 3/67?