What's the main differences between japanese and chinese?

Im guessing the grammer structure. The Japannese uses supfixs, prefixs. Do Chinese use?

ok.. so my chinese lady was good in giving me the dictionary.. i like chinese food, and shes right around the corner, so i get to know the owner pretty well.. but i had a hard time finding out about the whole -fix thing altogether.. though i dont know much so im interested also i guess

well i think that you should learn chinese first but what kind of chinese do you want to learn? contonese or mandrain? i know both but contonese is much easier and now i'm trying to learn japanese and it's much easier for me becausesome of them are like chinese so yeah i think it's chinese!

i was just wondering since there are different dialects in chinese are there different ones in japanese

aww mann people are saying Chinese is harder.I wanted to learn that.
Never mind now.Lol i`ll try to learn japanese instead.

Well, before I was into Japan, I was into China, but since I was young, the whole concept of their language was kind of hard for me to get to.

However, I found out that Japanese is much easier for me. ^^ I tried taking up Chinese once more last year, and PHALED. xD So I'm just sticking with Japanese.

However, these people here are giving sound advice, and everyone's case IS different, so I say consider both and hopefully you can make a decision soon. :)

i think [mandarin] chinese will help you with ur japanese (that is if ur very devoted). the only reason i think this way is b/c i'm a native speaker of mandarin and i learn japanese a lot quicker than, say, the average american (no offense) who is equally as devoted cuz i have the advantage of knowing the definition of kanji so i can concentrate wholly on pronunciation. but, idk... maybe someone who is japanese native speaker can tell you the opposite... just choose the one you would be willing to be more devoted to, k? good luck =)

I recommend not going anywhere near the Chinese language.

As a speaker of a Eurasiatic language, Japanese will be MUCH easier.
If you must learn a non-Japanese Asian language, I would recommend Korean.