Translation:Candy is sweet.
I can see a phrase like "sweet rain" from a native English-speaking author as well, maybe in a description of country life somewhere.
The interpretation of あめ as candy would have to come from context, kanji, intonation(?) or dictionary hints. So I also don't like this question
What is 'candy' in English?
Japanese words 'アメ' and 'キャンディ' is almost same. And I confirmed Duolongo's pulldown. It shows 'あめ candy candies'. So I believed 'アメ' is 'キャンディ'. And I believed 'キャンディ' is 'candy', too.
But when I have read hmmd_hyyさん comment, I felt something. And I searched 'candy' in the internet. Something odd.
And Japanese candy like this...
In Japan, The 'KitKat' is not 'キャンディ'.
I want to hear your opinion. I am waiting. (°▽°)
A KitKat can definitely be just "candy" in the USA but might be more likely to be called a "candy bar". I'm actually not sure that one of those is overwhelmingly more common in that case, but candy can be understood as pretty much anything with sugar in it.
Hard or soft, chocolate or fruit-flavored... but not baked goods and ice cream, those are their own categories. Now that I start thinking of it, there are probably more exceptions...
I should say that some people probably would understand "candy" in the same sense as Japanese: hard candy like lollipops. But the very existence of the phrase "hard candy" shows that many people feel the need to differentiate this type of candy from other types, like licorice or M & Ms.
Despite the hard shell, I have never heard M & Ms or Skittles referred to as "hard candy". What are those called in Japan?
The appropriate translation for あめ（飴）is 'boiled sweets', or what the Americans call 'hard candy'. This includes lollipops, konpeito, toffee, sherbet lemon drops, etc.
お菓子 (おかし) is the same as 'sweets' in English, and includes all sweet foods, including cakes, custards and wagashi.
I don't think Americans have a word for お菓子. 'Candy' does not include things like cakes, custards and wagashi.