Pitch Accentに関して、たまに言葉の意味に強い影響があるらしいです。多分もっとあるですが、個人的の意見には下記の３つの言葉がトップスリー分かりづらいものです。

はし(橋)　対　　はし(箸)　この場合、大阪弁と東京弁のPitch Accentは逆です。
かき(下記)　対　かき(柿)
こじき(古事記)　対　こじき(Beggar…申し訳ございませんが、この言葉の漢字が知りません。)

どちらが低から高、どちらが高から低を覚えていません。普通の日本人に聞いても詳しく区別出来ないと思っています。

乞食, according to the input method.

For me, I struggled with Hiragana, just because it was all new to me. I find learning the kanji to be easy. I'm going to take a Japanese class for the first time in the fall, so wish me luck!

You should tell me if this sentence is right (structure wise)

熊は犬を食べました。

any advice on particles?

As far as I know, that's correct. Maybe you want to switch は with が though. What kind of advice on particles do you need?

私は去年の九月から日本語を勉強した。ライデン大学で勉強している。それから、毎週新しい「ことば」を教えている。けど、あまりよく日本語を話せません。

今週は、試験の週です。けど、歴史の試験しかありません。木曜日しかライデンへ試験しに行きます。

I just get confused with when to use wa (ha) or ga. or the other particles for that matter.

You use 'ga' when you're talking about the grammatical subject, but with 'ha' this isn't always the case. (For example, you can give direct objects the 'ha' particle).

Or, when you want to talk about two things that are not the same (... and I just forgot the common English word for this...)
このりんごは甘いですが、そのりんごは酸っぱいです。

甘い＝あまい=sweet
酸っぱい＝すっぱい=sour

But usually, ha roughly translates to 'the', while ga is 'a' (I thought that the English term for this is defined vs. undefined article, but I'm not sure)

The rest have easier basic rules, but some verbs have specific particles that they always go with. But you should just learn those as set expression.

私は去年の九月から日本語を勉強した


I got that sentence all on my own!! I'm so proud of myself!

Oh, and thanks for the advice, I've only been studing japanese on my own for a few weeks now but I'm getting along fine. I don't know why, but I have trouble learning Katakana .

This is my favorite Katakana word evar! ベッド. It always tickles my pickle when I write it!

I haven't tkaen any formal Japanese classes, and I just bought my first Japanese textbook today!

デニスさん、
「木曜日しかライデンへ試験しに行きます。」が分かりません。どういう意味ですか？

Ohayo. Watashi wa nihongo ga hanasu koto ga dekimasu. Demo kana to kanji o shirimasen. Motto narainakereba narimesen. Ichiban yoi no narau koto ga nani desu ka?

Soshite hai, watashi no nihongo wa sukoshi warui desu ne?