Pob lwc i'r plant gyda'r arholiadau, eatyourveg!
Dw i'n gwybod bod y newyddion am Groeg yn ofnadwy. :( Wnes i obeithio am pethau gwell o'r etholiadau, yn anffodus :(. Ond in ni'n byw yn Alexandroupoli, dim Athens, does dim trafferth yma, diolch byth. Mae popeth yn iawn gyda fy nheulu :)
Mae fy ngwr yn Groegwr (is that correct?). Wnes i gyfarfod e yma yn ei wlad e! Mae e'n siarad Saesneg, ond dyw e ddim wedi byw erioed yn Brydain, dim ond yma!
It might seem that my Welsh is getting good, but actually I'm lacking in some really basic things, like how to use 'ni' and I'm still not quite sure of the 'bod' relative clause or conjunction use! I just try to use it anyway and don't worry about mistakes. I'm sure if it is really incomprehensible someone will let me know! 
I'll tell you what I do - perhaps it will work for you or someone else too. I just use the self study lessons to give me a basic outline, some structures, if you like, and then I read what other people are using and try to learn from their usage. I have started reading a novel: "Hunllef" by Manon Steffan Ros in the Stori Sydyn series, (a good choice for a learner, I feel) and I am trying to learn from the use of language. I don't want to read lengthy lists of grammatical explanation - I just try to learn from examples of the language in use. I don't pretend it's easy, and there are lots of words I've had to look up, but once I've looked something up, I try to use it. Sometimes I will say a few sentences, sometimes I will try and write down a few sentences using the vocab or structure.
For example, what seems like hundreds of posts back, somone wrote "mae'r caws yn dod yn ei flaen"
From this I got:
"dod yn ei flaen" come along, progress
ei + blaen - mutation to f, therefore ei causes mutation
use of possessive pronouns with adjectives? look for further examples
Mind you, you do need to be quite dedicated to work like this!