This might seem a little picky but I did some search and didn't find a proper answer for it. I'm just being curious, when saying this sentence:
He's out doing the shopping.
Should the addressee necessarily know the stuff that are being bought? Or does "the" imply that the shoppings are the daily usual necessities only(eggs, milk, bread and etc)?
Was it the same if I said:
He's out doing some shopping.
or they would have meant differently?
This is a matter of interpretation, but absent other context I would take "the shopping" to refer to some kind of planned or routine shopping (probably groceries, unless there was context to suggest otherwise).
In contrast, I would interpret "some shopping" to refer to less routine, more casual/occasional shopping, like browsing the mall for shoes or something.
Some households have a fairly regular routine for going to a shop. "Doing the shopping" would be understood to be doing this major shop for the week's or the day's food. The context would not necessarily allow the listener to know exactly what was being bought. But we would expect it to cover the essentials for that day or week.
On the other hand "I'm doing some shopping" suggests a less organised trip. Not part of the regular schedule. Perhaps done for fun or to get something that's missing.
"I do the shopping on Thursdays, as it's quieter then."
"After work I did some shopping in the High Street, and I bought a new bracelet."
There are other expressions that are possible "He's out shopping" or "He's at the shops" for example.
