Last time I checked, Koichi forgot to include a lesson on へ (just something that slipped between the cracks, unfortunately). On the plus side, though, unlike the thousand uses for に, what’s mentioned above pretty much covers everything you need to know about it, except for the fact that when it’s functioning as a particle, it’s pronounced え.

The trick with subjective adjectives like ほしい is that when you want to use them for someone else, you need to use the auxiliary verb ～がる = shows signs of ~. The reason for this is that you are not them, so you don’t know for sure that that’s what they’re thinking. A fair percentage of Japanese grammar involves taking the appropriate perspective on a situation.

The formation is Adjective-stem+がる
For example:
ほしい -> ほしがる
食べたい -> 食べたがる
めんどう（な） -> めんどうがる

It conjugates as an う-verb (i.e. がる -> がった -> がらない -> がらなかった)

So, getting to the sentence at hand:
ひとみさん　は　くるま　を　ほしがらない = Hitomi-san shows signs of not wanting a car = Hitomi-san doesn’t want a car (The particle is を because it’s a verb now)

You can use ほしい as-is when asking someone else what they want:
ひとみさん　は　くるま　が　ほしい　ですか？

You can also say:
ほしい　と　思う = I think she wants
ほしい　と　言った = She said she wants
ほしいそう = I heard she wants
ほしい　かもしれない = She probably wants

Et cetera.

In-depth enough for ya? =P

Basically, it’s pronounced whichever way makes it easier to hit the next syllable. As, the power that generations of lazy speakers has over etymology.

すし, for example, is “sushi”, otherwise you’re trying to say “s-shi”.

Hah, whoops. I completely didn’t notice either. =P

Nomimono = drinks.

Oh, I could have gone waaay more in-depth. =P

For example, with movement verbs:
- へ and に have similar meanings, but に tends to put more emphasis on the destination, while へ puts more emphasis on the movement itself – something like the difference between “to” and “towards” in English.
- を indicates the route of travel.

公園に歩きました = walked to the park
公園へ歩きました = walked towards the park
公園を歩きました = walked through the park

Other functions for に:
- Marks indirect object (benificiary of verb being done)
- Marks the time
- Marks the surface on which an action takes place (e.g. in the sense of 紙に書きます = write on paper)
- Marks the purpose for doing a movement verb
- Marks location-of-existence

And so forth. =P

了 (ryou) is a noun.
終えます (oemasu) is a verb.

In “have you finished breakfast”, “finished” is the verb.

You’ve pretty much hit the nail on the head all the way through your post.

Yeah, a lot of this stuff doesn’t get mentioned in TextFugu. It’s a rather complex issue, but I kinda think Koichi’s simplification is an over-simplification, which misses the main point somewhat.

1. Yep
2. Exactly. At this point in your learning, you’re being taught how to speak like a textbook. However, just as people in English don’t go “Do you like breakfast?” “Yes, I like breakfast” but instead reply “Yeah, I do”, in Japanese you’d drop as much of the answer as is plain from the context, and just reply (はい、)すきです. Or even そうです.
3. That there’s the trick – it’s completely dependent on the context. Trouble is, even with the context it’s often ambiguous. The grammar dictionary notes that often when you’re making a contrast, the element being contrasted is stressed – “ME wa kirei” rather than “me wa kirei”.
4. Hah. いろ は きれい is practically screaming “contrast!” =P

め is the topic here. If the adjective was, say, すき (“do you like my eyes”), then “you” would be the topic, but since the question is “are my eyes pretty”, it’s the eyes that’s the topic. We’re back at the AはBがC struture. め　は　きれい is a perfectly acceptable answer to “are my eyes pretty”, because it’s the topic, but め　は　いろ　は　きれい is definitely a contrast, because you’d expect the the second は to be a が in the standard structure.