Learn Polish: Co do aktywności, ciągle monitorujemy wstrząsy. - As for the activity, we monitor the tremors continuously.

The compound preposition co do means 'as for' or 'regarding,' and it always requires the Genitive case. Since aktywność (activity) is a feminine noun ending in a soft consonant, its Genitive form is aktywności. Using co do is a highly natural way to introduce, limit, or shift a topic in Polish.

Ciągle often means 'still.' Why is it translated as 'continuously' here?

While ciągle is very commonly used in everyday speech to mean 'still' (as in 'I still live here'), its literal core meaning is 'continuously' or 'constantly' (it is related to the noun ciąg, meaning a sequence or continuity). In a technical or observational context like monitoring seismic activity, 'continuously' captures the intended meaning perfectly.

What case is wstrząsy here, and why does it look like the dictionary plural?

It is in the Accusative case because it is the direct object of the verb monitorujemy (we monitor). The base word is wstrząs (a shock, tremor, or jolt), which is a masculine inanimate noun. As a quick refresher: for masculine inanimate nouns, the Accusative plural is always identical to the Nominative plural, taking the -y ending here.

Could I use odnośnie instead of co do to frame the topic in this sentence?