Mall strolling is recreational activity, sometimes quite costly. why no article before activity?

Question

Mall strolling is recreational activity, sometimes quite costly.

This is a sample sentence in my text book. I am wondering why there is no article needed before activity?

this is modeled after this

Model: Dumpster diving is outdoor work, often surprisingly pleasant. --Lars Eighner, "On Dumpster Diving"

is this just a typo?

Answer 1

One could potentially make an argument for not using the article, based in the comparison to dumpster diving being "outdoor activity". However, I would say that having the article is more the common practice. We cannot rule out that this is not a typo in the textbook, and they did not truly intend it. Typos do happen- even in textbooks. Yet on a test, and especially on the SATs, I would definitely be safe and use the article. Using the article is definitely correct, while the other way could be seen as questionable.

Answer 2

You are right. That example has a typo. It should be "Mall strolling is a recreational activity, sometimes quite costly."

"Work" is a non-count noun, so you would never say "dumpster diving is an outdoor work."

"Activity" is a count noun, so you need "a" (or "the" sometimes) when it is in singular form.

Examples:

Golf is a fun activity.

Shopping and cooking are fun activities.