The usage of な to make an entire clause modify a noun, and "Alice is a desirable person" versus "Person that likes Alice"


In the very beginning of Tae Kim's Guide to Japanese, namely
[here](http://www.guidetojapanese.org/learn/grammar/adjectives), there is this
example:

> 魚が好きな人。
>
> Person that likes fish.

When I read that for the first time, still as a very beginner in japanese, I
just said "ok interesting, let's move on". But now, having completed the whole
"Basic Grammar" and "Essential Grammar" sections of Tae Kim's guide, and
drastically improved my vocabulary, I decided to reread everything and
stumbled at this example.

It sounded unnatural, strange. As if the phrase was saying **" fish is
desirable person"**. (Note: of course I am far from fluent, so I wouldn't be
surprised if it's correct, although sounding strange).

So I see two ways of parsing that phrase:

  * (魚が好き)な人
  * 魚が(好きな人)

**Question 1:** As far as I know (and here is where I'm probably wrong), we
should use **な** to connect **na-adjectives** to nouns, but the first way of
parsing is using **な** to connect **a whole clause** to a noun, is this
grammar really correct? Does the whole clause accept a **な** simply because it
ends in a na-adjective? **What is going on here?**

**Question 2:** Clearly the second option ("fish is desirable person") does
not make sense, but I think we can create a similar example in which both
interpretations would fit:

  * "person that likes Alice": (Aliceが好き)な人
  * "Alice is (a) desirable person": Aliceが(好きな人)

If this is correct, then is guessing by context the only way to decide between
the two interpretations?

* * *

_Note: I didn't post these as separate questions because they are extremely
related and there is a chance that a single explanation might help me with
both questions._




### Question 1

As Tae Kim's guide says, relative clauses cannot end with だ, so you cannot say
魚が好きだ人.

> The negative, past, and negative past conjugations of verbs can be used just
> like adjectives to directly modify nouns. However, we cannot do this with
> the plain non-past state-of-being using 「だ」. (I told you this was a pain in
> the butt.) The language has particles for this purpose, which will be
> covered in the next section.

And in the next page, it says you need to use な for cases involving na-
adjectives anyway:

> Even when substituting 「の」 for a noun, you still need the 「な」 to modify the
> noun when a na-adjective is being used.

Apparently that page lacks an example for this pattern, but basically whenever
you can say `A + は + B + が + na-adj`, you can turn it into a relative clause
and say `B + が + na-adj + な + A` (or rarely, `A + が + na-adj + な + B`, as
described below).

  * そのスマホはCPUが高性能だ。 (The smartphone has a high-performance CPU.)  
→ CPUが高性能なスマホ (a smartphone with a high-performance CPU)

  * その生徒は成績が優秀で将来が有望だ。(The student is academically excellent and his future is promising.)  
→ 成績が優秀で将来が有望な生徒 (a student with high grades and promising future)

### Question 2

アリスが好きな人 is indeed ambiguous and means both "a person whom Alice likes" and "a
person who likes Alice". This ambiguity has been asked several times, so
please read [my previous
answer](https://japanese.stackexchange.com/a/30172/5010).

