Please correct my "essay"

[Llawygath]

Noswaith dda.
A while back I wrote up a short narrative (in Welsh) about a couple of cats and a dog. As I learned more words, it eventually grew to include some children and their parents. However, it turned out that the children had somehow gotten terribly lost, and I decided that I wanted to explain that somehow. What follows is my attempt at a reasonably coherent explanation.

Y plant sydd tros y môr

Ble mae'r plant? Ydy'r plant yn y môr? Nag ydyn, mae'r plant tros y môr.
Mae'r plant wedi nofio oddi tad oherwydd mae hufen iâ 'da fe. Dim posibl!
Mae mam, tad ac y plant yn byw yng Nghymru ond dydy'r plant dim yng Nghymru nawr, maen nhw yng Nghanada. Dydyn nhw ddim yn hoffi Canada. Dydy'r Gymraeg ddim yn cael ei siarad 'na, dim ond y Saesneg ac y Ffrangeg. Dydy'r bwyd dim yn dda ychwaith.

Pretty short so far. I may be adding more to it periodically, but for now this is all I've got.
I'm quite sure I've failed on both the coherency and the sensibleness, and I've not done too good a job of sticking to facts either. Feel free to suggest ways for me to improve the realisticity of it -- I'd love to hear story suggestions.

But I'm mostly looking for grammar advice. I'm not sure about oddi; the meaning I wanted was 'away from', but I think oddi can also mean 'from under'.

[Lurch]

Bore da, Llawygath!

Can't give you help with grammar, but for realisticity, maybe the children could have gotten on a ship to Canada by mistake, rather than swimming all the way to Canada.

[linguoboy]

But I'm mostly looking for grammar advice. I'm not sure about oddi; the meaning I wanted was 'away from', but I think oddi can also mean 'from under'.

As far as I know, oddi isn't used as an independent preposition in Modern Welsh outside of fixed expressions like oddi cartef "away from home". Otherwise only in compounds like oddi ar "off of", oddi mewn "from inside", or oddi wrth "from [a person]". But oddi wrth Dad sounds odd to me with a concrete subject, so I would simply use o.

I have seen oherwydd followed by mae but it's better form to use bod.

[Llawygath]

Bore da, Llawygath!

Bore da, Lurch! (Love your username, by the way.)

Can't give you help with grammar, but for realisticity, maybe the children could have gotten on a ship to Canada by mistake, rather than swimming all the way to Canada.

By mistake...hmm. Hadn't thought of that approach. I did think maybe I could somehow have them take a ship/boat, but I can't recall the right word -- I'm only coming up with bád, which is Irish and not Welsh. I'll go ask y geiriadur mawr right now:

boat 1. ysgraff n.f. (ysgraffau) bad n.m. (badau) cwch n.m. (cychod)
ship 1. llong n.f. (llongau)

Ffw, now I don't know what to do. Three words for boat? Seriously? Have they slightly different meanings with them?
And then there's the question of which verb you use if you want to take a boat/ship. I'd probably have to ask my phrasebook, as I think they discuss this aspect of traveling.

[Llawygath]

But I'm mostly looking for grammar advice. I'm not sure about oddi; the meaning I wanted was 'away from', but I think oddi can also mean 'from under'.

As far as I know, oddi isn't used as an independent preposition in Modern Welsh outside of fixed expressions like oddi cartef "away from home". Otherwise only in compounds like oddi ar "off of", oddi mewn "from inside", or oddi wrth "from [a person]". But oddi wrth Dad sounds odd to me with a concrete subject, so I would simply use o.

Diolch.

I have seen oherwydd followed by mae but it's better form to use bod.

So [...] oherwydd bod hufen iâ 'da fe? It seems strange to use a verbnoun there. What if you have a conjugated form of bod other than mae after oherwydd? You can't replace that with bod too, can you? You'll remember this sentence:

Oherwydd maen nhw yn y sŵp.

(The topic was why I didn't eat mashed potatoes; nhw refers to the potatoes in question.)

[linguoboy]

It seems strange to use a verbnoun there.

Why? English does this sort of thing all the time, e.g. "Now I slid into a parked car due to there being ice on the road."

What if you have a conjugated form of bod other than mae after oherwydd? You can't replace that with bod too, can you?

Of course you can. It works just like English:

"because he was sick" > "due to his being sick"
"because they were sick" > "due to their being sick"

[Llawygath]

It seems strange to use a verbnoun there.

Why? English does this sort of thing all the time, e.g. "Now I slid into a parked car due to there being ice on the road."

What if you have a conjugated form of bod other than mae after oherwydd? You can't replace that with bod too, can you?

Of course you can. It works just like English:

"because he was sick" > "due to his being sick"
"because they were sick" > "due to their being sick"

Sorry, at first glance I fail to see the connection between the two forms. Let's see if we can get this to make sense:
- oherwydd bod hufen iâ 'da fe is <because [of there] being ice cream with him>
- because [of] there being ice cream with him is <oherwydd bod hufen iâ 'da fe>
- because [of] ice cream's [<=>] being with him is <oherwydd bod hufen iâ 'da fe>
Okay, okay, I think I get it. Thanks. But how about in other tenses? Do you say oherwydd wedi bod hufen iâ 'da fe or something if you want past tense? What about future? Am I asking too many questions at once?

[linguoboy]

Thanks. But how about in other tenses? Do you say oherwydd wedi bod hufen iâ 'da fe or something if you want past tense? What about future? Am I asking too many questions at once?

You may be trying to run before you can walk. You don't even know any past or future tense forms of bod yet, do you?

It depends whether you're talking about absolute tense or relative tense. The bod clause has the same absolute tense as the rest of the sentence, just like a gerundive does in English. If you use wedi in the bod clause, it is the equivalent of using a perfect gerundive in English and implies that the relative tense of the two clauses is different:

oherwydd bod wedi bod hufen iâ 'da fe
"because of there having been ice cream with him" ("because of his having had ice cream")

[Llawygath]

Thanks. But how about in other tenses? Do you say oherwydd wedi bod hufen iâ 'da fe or something if you want past tense? What about future? Am I asking too many questions at once?

You may be trying to run before you can walk. You don't even know any past or future tense forms of bod yet, do you?

Ydw.
Roedd y gath yn cysgu ddoe. Fydd y gath yn cysgu yfory. (Stupid sentences yes, and I could fill out a verb table but don't feel like it.)

It depends whether you're talking about absolute tense or relative tense. The bod clause has the same absolute tense as the rest of the sentence, just like a gerundive does in English. If you use wedi in the bod clause, it is the equivalent of using a perfect gerundive in English and implies that the relative tense of the two clauses is different:

oherwydd bod wedi bod hufen iâ 'da fe
"because of there having been ice cream with him" ("because of his having had ice cream")

All right, that works. I'm trying to think of how you do it in English, and I'm pretty sure the clause has to agree in absolute tense with the rest of the sentence:
- The children swam away from dad because he had ice cream with him.
You can't really say because he has ice cream if the other, non-dependent clause is in the past tense (that is, if you're only talking about past events with no reference to the present); it just doesn't fly. You could say because of his having ice cream, which is the parallel construction to Welsh, but that's less common. That aside, I see your point -- the construction we're learning isn't supposed to have tense markers in it unless its relative tense differs from the tense of the rest of the sentence.

[Llawygath]

Seems nobody's been here today.
During some class or other at school (bad Llawygath) I wrote up a dialogue that's supposed to take place between the children's parents. It should probably go here, so I'm going to post it.
*after looking for it in school binder* Looks like I'm going to have to do it from memory. My binder barfed this morning -- or was it last night? -- and the contents are slightly jumbled. Anyway, here goes something:

Mam: Ble mae'r plant?
Tad: Dw i ddim yn gwybod.
M: Wyt ti ddim yn gwybod?!
T: Nac ydw. Dw i wedi eu colli nhw.
M: *tsk* Ydyn nhw ddim yn y môr?
T: Nac ydyn. Tros y môr.
M: Tros y môr? Dim posibl!
T: Maen nhw'n gallu nofio, on'dydyn?
M: Ydyn, ond dim tros y môr.

And I think it ends there. There might have been more had I spent more time on it, but my class time got eaten enough as it was so I decided to stop using it to write random nonsense.

There was also an attempt to write this messy thing into a coherent story, which failed after the first sentence. It went like this:

Tipyn o amser yn ôl roedd teulu'n byw yng Nghymru: dau riant; tri plant; cath a ci.

I didn't think much of that sentence when I wrote it and I still don't. I'm not even quite sure how to express the idea I wanted in French, and when I can't say something in French there's a safe bet I won't know it in anything else that isn't English. (That last sentence was supposed to say something else. I think I may be incoherent from lack of adequate sleep.)
So feel free to correct more of my nonsense, everyone. Diolch linguoboy a Lurch!