'that' modifies interplay. This can be understood only by considering the sentence until its end. Interplay is between 'nature' and 'imagination'. Here 'nature' is related to "external world of sensory experience" and 'imagination' is related to "the internal workings of the mind in contemplation".

If you have noun+prepositional phrase+that, then the clause that follows "that" modifies the original noun (the one being modified by the prepositional phrase).

As mathbyvemuri said, "interplay" is being modified. "Between nature and imagination" is a prepositional phrase that modifies "interplay."

Bill,

In this case, "interplay" and "nature and the imagination" are both nouns. If "that" here refers to "interplay," how would you attach a "that" phrase here if you want to modify the "imagination?"

Isn't that phrase modifies immediate noun that preceeds it? If it is so, isn't noun imagination closer than the noun interplay?

"Imagination" is closer, but it's in a prepositional phrase. A relative pronoun (like "that" and "which") can be used to modify the noun immediately before it, but it can also be used to modify a noun further away if the pronoun and the noun being described are separated by a prepositional phrase. To figure out which one is being modified, we have to understand the rest of the sentence. The rest of the sentence describes the "external world of sensory experience," which corresponds to "nature," and the "internal workings...", which corresponds to "imagination." We can see that the "that..." phrase is meant to modify both "nature" and "imagination", so it must be modifying the "interplay" between them.

The easiest way to use a "that..." phrase to modify "imagination" would be to rewrite the sentence so that "imagination" is not in a prepositional phrase.

bellcurve wrote:In the simple plays, such as You Are Good, and the lyrical meditation of John Smith, Robert achieves an interplay between nature and the imagination that explores both the external world of sensory experience and the internal workings of the mind in contemplation.

What does the underlined portion modifies? I am confused on whether it modifies "imagination" or "interplay."

Discrimination in wages that blah blah.....

Can the modifier "that blah blah..." modify "Discrimination" or it has to modify wages?

In another words if you have "Noun1 + preposition + Noun2 + that modifier," can the modifier modify the first noun? Or is it that it always modifies the second noun?

Thank you for your help.

Interesting question bellcurve, thanks for bringing it up!

Bill -

Is it solely the context that always decides whether the original noun or the noun in the prepositional phrase is modified? Does it depend on the kind of modifier - relative modifier, essential/non-essential modifier, etc.?
Please advise.

How about the following sentences?

The Principal tried to calm the worried parents of the students who had disappeared in the storm.
An ice sheet covers 80 percent of the surface of Greenland, an area roughly the size of Alaska.
The recent earthquake destroyed the library at Alexandria, the largest of the ancient world.
Obama was recently elected the President of United States, the country which has the world's richest people.

Thanks
Sunny