Translation:The supermarket is making a profit.
brabúis. The direct object of the verbal noun in the progressive is (generally) in the genitive.
galaxyrocker, would you please explain the "uis" instead of just the "us " in this word. When later in the lesson they asked to translate "profit", I spelled "brabuis" and it was marked incorrect. So, as usual, I'm confused again!
The ag + verbal-noun construction (ag déanamh in this case) causes the following noun to be in the genitive, and brabúis is the genitive form of brabús.
ag déanamh sounds like [idjinna] here, with the stress on the initial i. I really could not pull out "ag déanamh" after numerous tries. Is this how it is pronounced in some parts of the country, or by some speakers?
It's an example of "cup of tea" syndrome.
English speakers often elide the "f" in "of" in normal speech. In Irish, the "g" in "ag" and the "n" in "an" are often elided too. There is no hard and fast rule - just as the "f" in "of" is sometimes spoken, and sometimes not (even by the same speaker), depending on the cadence of a particular sentence, or the formality of the setting, and it doesn't cause a problem for other English speakers, because we subconsciously "hear" the "f", even when it isn't there, the elision of "ag" and "an" is just part of the normal rhythm - sometimes they will be articulated, sometimes they won't. In a sentence like this, an Irish speaker "hears" "ag déanamh", just as an English speaker "hears" "cup of tea", even when the speaker elides the "f".
De Bhaldraithe used déanamh in his 1959 English Irish Dictionary
To bring in, yield, show, a profit, brabach a dhéanamh; brabach a bheith ar rud. To sell sth. at a profit, brabach a dhéanamh ar rud a dhíol; bheith buaite le díol ruda. To make a profit on, out of, a transaction, brabach a dhéanamh ar bheart gnó.
Dineen doesn't have an equivalent example, but he has plenty of uses of ag déanamh that probably fall outside your understanding of déanamh:
ag déanamh coimhightheasa - "making strange.
ag déanamh ar an gcathair - "making towards the city"
ag déanamh grinn ar - "making fun of"
ag déanamh saoire - "spending a holiday"
Is féider leat brabús a thuilleamh freisin, ar ndóigh.