"Where are the children running to?"
Translation:לאן הילדים רצים?
This is the answer I got from the Facebook group:
In hebrew you can usually put a preposition before question words, the words לאן, להיכן are actually the question words אן (rarely used by its own) and היכן with the preposition ל (to) and therefore both of them (along with לאיפה) have this mentioned meaning. another examples:
למי = whom, to who מהיכן, מאיפה, מאין = from where למה = for what (pronounced le-ma)
to say "where in" however, you say איפה ב...
Well, that is the problem with English and with a computer teaching a language. "where" can be both about location and about direction. Hebrew, like many other languages, has two different words for those. איפה asks about location and לאן asks about direction. And the system offers איפה because that word is more common. The system doesn't recognize context, which is why hints for Hebrew are very bad. That is what you, as a learner, need to know the difference and to recognize when to use which.