Please clarify the grammar used in the sentence below.
Most museums provide hands-on activities suitable for both children and adults.
Question: Why is the adjective "suitable for" placed after the Noun "activities".
In English (unlike some languages, eg German and Japanese) an adjectival phrase or clause cannot usually precede its head noun. An adjective can, but once the adjective has a complement it cannot.
The usual way of analysing this kind of construction is as an example of whiz deletion: it is a relative clause ("which are suitable for both children and adults") with the "which are" omitted.
Colin Fine's answer about whiz-deletion is correct, but I think there's another aspect that needs to be explained.
The adjective "suitable" isn't a stand-alone adjective here. It's part of a longer descriptive phrase "suitable for both children and adults". If we wanted to put that in front of the noun, it would be very difficult to understand:
Most museums provide hands-on suitable for both children and adults activities.
We could hyphenate it to make it work:
Most museums provide hands-on suitable-for-both-children-and-adults activities.
but it's still a bit of a mouthful; when saying it out loud you have to run all the hyphenated words together to make it clear that they're hyphenated.
If we just moved the word "suitable" to be before the noun, it would change the meaning:
Most museums provide suitable hands-on activities for both children and adults.
would mean that the museum provides activities for both children and adults, and that these activities are suitable. But it doesn't say what "suitable" means - do the activities take a suitable amount of time? Are they suitable for a rainy day? For a sunny day? It's unclear.
So, we tend to phrase this in English as:
Most museums provide hands-on activities that are suitable for both children and adults.
Then, as Colin Fine says, we then omit the "that are" because, by convention, it's not required.