I asked a similar question elsewhere in this exercise (the one about taking someone's coat). Why would "She takes his shirt off" not be accepted? What does "takes his shirt from him" mean here? Does it mean she takes his shirt off (because he's passed out in a drunken stupor) or does it mean, he has taken it off himself and he gives it to her?
I think "She takes his shirt off" wouldn't be accepted, because she could be wearing his shirt, in which case the sentences would not mean the same thing (ie, she takes it off herself, vs she takes it off him).
As for your second question, I think "she takes the shirt from him" would be "Tógainn sí an léinte de" (but someone please correct me, if I'm mistaken). I think galaxyrocker mentioned that bain...de means "remove (an article of clothing) and "tóg" means "take (something from someone)".
regarding "an léine de" it sounds like she is saying un Lyain-uh dih
There seems to be a kind of swallowing of the l here, or making it an ly sound
in English say "Only yeah" really fast and that is an approximation to what I think I am hearing as far as the ly sound goes ... not the rest of it.
That's what a "slender l" sounds like, though how obvious it will depend on both the speaker, and the context that the word is spoken in.
In the pronunciation of léine on teanglann, you can hear that "ly" sound from the Connacht speaker, but not really from the Ulster speaker. On the other hand, for léinseach the Ulster speaker has a more "slender l" sound than the Connacht speaker.
Munster Irish doesn't "slenderize" it's consonants nearly as much as Ulster and Connacht - even s, where the difference between slender s (seo) and broad s (sa) is obvious, even for beginners in the language, is sometimes lost in Munster, where anseo becomes ansa.
Baineann sí an léine di.
Baineann sibh bhur gcótaí díbh - "You take your coats off" https://forum.duolingo.com/comment/13532705
Baineann sé a chóta de - "He takes his coat off"
Baineann tú díot do hata - "You take your hat off"
Bainim díom mo chóta - "I take off my coat"
Bainim mo chóta díom - "I take my coat off"
They use different prepositions. De is used with bain to mean "take off." For "to" in the sense of "give to" you would use the preposition do. So she's not giving it de him, as you say, but rather giving it do him.
For de you have:
For do you have:
Also note that there's two other prepositions that could be translated as "from": ó and as, though as means from more in the sense of "out of."