"Six fish are swimming in the pond."
Agreed, it was で in a different sentence when a girl was swimming in the pond...getting very confused by the Nature lesson
The thing is... when you start a action in a place you use で that was the girl's case... But when the action is happening all the time you have to use に. Didn't you already see some fish swimming on the earth and after it going to swim in the pond right? Hahaha
But there's a browser plug-in you can get that can show you the hiragana if you can't get it from context. I think I am using Yomichan.
I'm always confused about the order of things and where to put each part of the sentence... I answered いけにさかな六ぴきがおよいでいます and got it wrong, but I'm not sure exactly where to correct it... Should the particle (が in this case) always come before the number/counter?
が is to mark さかな, so it has to go directly after it. As someone above stated, the counting part is linked to the verb, "six living things exist". So this part goes in front of the verb. That's how I see it anyway.
I was marked wrong--I put "sakana ga ike ni..." instead of "ike ni sakana ga...". Is this really 'wrong', and if so, why?
I'm not 100% on this but I'll give you my thought process on how I got the answer. When counting, the structure is usually "object が number(and it's counter) verb.
So if I were to take the core of this sentence, which is "there are six fish," it would be さかなが六ぴきいます.
If you add more descriptions to this core like "in the pond" or "swimming," you'd build around this sentence structure. That's how you get the answer given.
Why is ぴき here and びきin the case of two animals, also i see ひき in other exercise, what is the difference?
The pronunciation of the counter gets rendaku-ed in different ways depending on the number.
8 This says it can be はちひき or はっぴき (not sure when each would be used)