Use of plural with the word activité in the last phrase

Question

Dans ce-phrase-ci, pourquoi "d'activité" n'est pas pluriel?
"...ainsi que certains domaines d'activité tels que..."

Accepted Answer

les domaines d'activité -- certain areas of activity
Note that "activity" isn't in the plural in English either (they are not "areas of activities").

Answer

Bonjour Karen,
Here you are referring to "activité" in a  "generic sense" and not in a "countable sense" or in a "specific way".
I hope this is helpful.
Bonne journée !

Answer

Salut Karen,"... certains domaines d'activité ...""certaines"  is the plural adjective modifying "domaines" and these are domaines of activityHope this helps.Bonne journéeJim