I dont know what process you followed, but you're wrong - the only "m" sound in this sentence is in the word maith. The "n" in lena is very clearly an "n".
Here are some examples of what is maith liom sounds like:
Is maith liom an t-earrach
Is maith liom an doras bán
Is maith liom an rothar glas
Is maith liom a bláth
Note that I agree that this exercise is quite difficult to hear and properly parse when you first encounter it, but it's not because the "n" in lena is mispronounced.
This is the reason I ran away from learning for a while. Just no way I can remember all this, especially without hearing it spoken. These little things need so many more lessons to be learned and I am having trouble filling in the gaps. Here you have told us just one instance with one noun....so many others to learn....it's a bit overwhelming at times.
The tips are only available on the Duolingo Website, and are displayed immediately below the list of lessons when you select a particular skill.
Duolingo will detect a web browser on a mobile phone, and will (usually) display a "mobile friendly" version of the site that does not display the Tips & Notes.
EDIT - Since the recent website redesign, the Tips & Notes are now available on Mobile devices - click on the light-bulb icon next to the Start button in a Skill to see the Tips & Notes for that Skill.
It truly is. I feel much the same way .... I'm just accepting that it'll be a really long process. I've already tried and given up a few times. This time it's finally starting to gel. In tutoring sessions, I still feel like a blithering idiot, but it's pretty exciting when, over the course of a day, I find myself now able to describe what I'm doing in Irish ....
It works the same way because it's the same "a".
To say "X likes" you say "Is maith le X". When X is a pronoun, "le" combines with the "X", so you get "liom" instead of "le mé", "leat" instead of "le tú", etc.
When X includes a possessive pronoun, (my brother, his cat) the possessive pronouns that start with a vowel are combined with the "le", so you get "lena" and "lenár", and the "a" and "ár" continue to trigger lenition and eclipsis as usual.
In English, "him" is a pronoun and "his" is a possessive adjective. "with him" is leis and "with his" is lena. When the object is feminine, English uses the same word "her" for both the pronoun and the possessive adjective, but the Irish for "with her (pronoun)" is léi and "with her (possessive adjective)" is lena. When translating "with her", you have to figure out which "her" you mean - that's not a problem for "him/his" or "them/their".
It might be clearer in an example like
rithim leis - "I run with him"
rithim léi - "I run with her"
rithim lena mhadra - "I run with his dog" (rithim le + a mhadra - lenition makes it "his")
rithim lena madra - I run with her dog (rithim le + a madra - no lenition makes it "possesive her")
To complicate things just a little bit, there are actually 2 different versions of leis - it can mean "with him", (le + sé) as above, but it is also used when le occurs before a definite article, so rithim leis an madra means "I run with the dog", and rithim leis na madraí means "I run with the dogs".
Thanks for spelling this out.
I can't see any mention of the construction/word "lena" = "le" + "a" in the "tips" section for this lesson.
I suspect the insertion of "n" is so obvious to a native speaker that it in turn simply throws us learners with close to zero input outside duolingo.
For socio-political reasons, Irish doesn't have an agreed standard pronunciation, just a range of regional/dialect pronunciations. The Caighdeán Oifigiúil that the course is based on more or less standardizes the grammar, and there are de-facto standard spellings in Ó Dónaill's Foclóir Gaeilge-Béarla, de Bhaldraithe's English-Irish Dictionary, and Foras na Gaeilge's New English-Irish Dictionary.
The problem with what you hear can often be simply the Irish accent. When my parents spoke in English , the ‘e’ was never said as in ‘egg’ but more a cross between the English ‘e’ and ‘i’. So when I hear the pronunciation of ‘Lena gcat’ sounding like ‘ ‘linn a got’ , it sounds just as it should. Like it’s being said by an Irish person .