Again, as with writing “I am” there are several informal and formal, written and spoken forms of “we are“.
The least formal, spoken form is “Dyn ni” in the South, “Dan ni” in the North. Apparently we also use “yn ni” in the South, but not here in South East Wales. Not in this decade anyway.
Adding the “Ry” makes a more formal “Rydyn ni” or “Rydan ni“. “Rydyn ni” is not limited to South Wales, being the more commonly used of the two. We also see written “Ryn ni“- whilst seen in written work, this is informal language.
“Rydym” with or without the “ni” is the more formal version. “Ni” becomes unnecessary, as “Rydym” indicates “we” without it. In fact, most of the other forms indicate their person, but as we write more formally, we drop the pronouns “i”,”ef/fe/fo”, “hi”, “ni”, etc.
Finally, the most formal written form is “Yr ydym” (again with or without the “ni“).
“Yr ydym yn + verb” – most formal.
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