I'm with you on this one, SM. And, one could argue that "The rain will stop soon." is actually a better translation, because that's would English speakers would actually say. It's funny, the lesson material seems to stress word-for-word literal translations, but, then when you work on the real-world translation material, word-for-word literal translations are just about always a poor choice.
Not actually true. Like many translations it just depends on the context, but I appreciate that the right context doesn't always spring directly to mind.
Eg: You are introducing your favourite film to someone. They ask you half way through why the main characters don't get out of the rain and under cover. You reply: "It doesn't matter. The rain stops soon."
That's a fun example, and I see your point: there aren't many sentences which wouldn't make sense in some sort of hypothetical context. However, if a language learner is interested in "sounding native" (and if they're not, that's fine, too! Function before style points...) then it's useful to know that, in basically any normal everyday context (where the speaker doesn't know the future outcome with certainty), "The rain stops soon" is not a native utterance. I wouldn't call that information pointless, but I would also never fault anyone for not caring how "native" their language sounds (Hauptsache: man versteht, und wird verstanden!)
The problem is English. We do not use the present of action verbs to talk about the present. If we say It rains we are talking about the habitual situation. It rains in the winter months. If it is currently in the action of raining we say It is raining. It is as if we use present for the present imperfect and the imperfect present for the present! No wonder us English speakers have such a hard time learning tenses and conjugations!
"To throw" means to toss something through the air, but "To throw up" means to vomit.
There are lots of examples in English (it may be more common in Germanic languages?) Like "to show" vs. "to show off", or "to give" vs. "to give up", etc... Adding (or changing) a participle changes meaning, often fairly drastically.
In German, the near (and sometimes less-near) future is often expressed with the present tense (whereas in English, that is far less common, e.g.: "The movie starts in 5 minutes." or "Next month we fly to Italy.") So actually, it's easy for English speakers to over-use the future (werden +), in situations where a native speaker would more commonly just use the present. ("Am Freitag fahre ich mit Freunden nach Cleveland.")
I don't think that's idiomatic German (as in, it isn't one of the ways they say that), but a native speaker can chime in here with a definitive answer! Sometimes a more "obvious translation" works (English & German are closely related!) Often, they don't quite, though they may effectively express the desired meaning (in a non-native way.)