On one of the other questions in this section, someone said that "Gymraeg" was the feminine form of "Cymraeg" because the question was describing a female teacher. Which part of this sentence is feminine? Or is Gymraeg the only feminine form word here and it's just an assumed female speaker?
I guess you could consider "Gymraeg" the feminine adjective form of "Cymraeg". The reasom it has mutated here is because "Ysgol" is a feminine noun which means adjectives starting with T, P, C, D, G, B and M mutate softly after it.
If I get this right, this is a special school for teaching Welsh language, right? Shouldn't then "a school for Welsh" be accepted?
Not quite an "Ysgol Gymraeg" is a school that teaches through the medium of Welsh and in this instance "Cymraeg" is acting as an adjective to "Ysgol" which is translated as "Welsh school".
Why wasn't "Welsh speaking school" accepted? Whats the difference between that and a Welsh-medium school?
What you said makes sense but I think it can be open to misinterpretation perhaps. What they mean here is that it's a school that teaches in Welsh (through the medium of welsh), whereas a Welsh speaking school can be one that teaches in mostly English but provides lessons on the Welsh language or uses Welsh phrases amongst English. Hope this makes some sort of sense?
Welsh medium and welsh speaking mean the same thing my answer was correct