"Os" versus "Taswn i....mi, faswn i"

During the Intermediate Course so far,I have been having
difficulty guessing when to use “os” and when to use “taswn i”. Along with
this I have been a little confused about when to follow “os” with the future
tense. Now i’ve been thrown by the use
of “ydy” rather than “mae” in some cases in “os” clauses.

Being curious I looked up “If” in my Modern Welsh Dictionary
which explained that the usages reflect the difference between conditions that
are open (likely) and those that are closed (unlikely or unreal).

(Pe) taswn (clause),
mi faswn (clause) (conditional clause)

I would (do this) if (this unlikely condition)

Taswn i’n poeni mi faswn i’n mynd i’r feddyg


Os + future tense (though sometimes present tense)

If this (quite likely condition) occurs (will occur in
Welsh) then……

Os bydda i’n dod yn gynnar, byddwn ni’n medru mynd am tro
(os + future)


Os ydy’r ddynes yn teimlo yn unig, bydd rhaid inni mynd i
weld hi (os+present)

I now see that it is a grammatical rule in Welsh that in “os”
clauses, the use of the 3rd person singular present tense requires “ydy”
rather than “mae”.

What I can’t get my head around is whether, on the street,
real Welsh people analyse what they want to say in conversation before choosing
which version. I don’t need to in English but I’m quite sure that I shouldn’t
be able to if it were grammatically necessary. In practice does it matter?

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And now it does :slight_smile:

S’mae Gerald?

I would say that there is no way anyone does this. They just use patterns they have learned from continual usage that feel/sound right in the circumstances. This is no different to how we learn with SSiW really, and is reinforced if you are lucky enough to be exposed to a lot of Welsh conversation with first-language speakers (you copy their usages, which could vary by locality). Colloquial usages are never going to match the grammatical “rules” you read in a book 100%, because people speak naturally without recourse to such rules. The best thing to do is get involved with conversations as much as possible and not worry about fine detail such as this; the bottom line is that you will be understood.

Having said the above, there are plenty of people on the forum who have a solid grounding in grammar, who will be able to supply details regarding the os pattern and the taswn…mi faswn pattern.



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Thanks, Stu,
So I won’t come across as a total Saes plonker if I use the wrong option of “Os” as against “Taswn…”?

Absolutely not! :sunny:

Absolutely not! :sunny: