Verb agreement between target language doesn't agree. Strictly speaking, ありました is past tense so "am" should be past tense. 2.) 財布を落とす恐れがありました。 I "was" afraid I had lost my wallet. 3.) 事件の恐れがありました。 I "was" afraid there was an accident. As for 1, it seems that the Japanese is a bit awkward but understandable. Perhaps we will need a native speaker to make sure--but, I think this would be better: パーティーの為に食べ物が足りない恐れがあります。 I am worried that there is not enough food for the party. or just パーティーに食べ物が足りない恐れがあります。 I am worried that there is not enough food for the party.

(2) 財布を落とす恐れがありました。 →財布を落とした恐れがあります。 I am afraid that I have lost my wallet. If you use 落とす, it means you lose the wallet in the future.

「恐れがる」--> 恐れがある (1) パーティーはじゅぶん食べ物じゃない恐れがありました。 --> パーティーにはじゅうぶんな食べ物がないという恐れがあります。 I am worried that there is not enough food for the party. (2) 財布を落とす恐れがありました。 --> 財布を落とす(or なくす) 恐れがあります。 I am afraid that I have lost my wallet. (3) 事件の恐れがありました。 --> 事故だった恐れがあります。 I am afraid there was an accident. You wrote "I am..." and it means 恐れがあります(present). As Jieiko-san said, 恐れがありました is "I was...". I hope this helped you.

I had a look at the site; it is awesomely organized. I wish that I had such resources available to me when I first took up studying Japanese. By the way, that is a great goal striving to learn one new grammar rule per day. 頑張って下さい。

りょこさん：　分かりました。　ありがとうございます！