Several ponderings

[el.fast_513579]

I'm trying to do some Japanese exercises. Yay! Took me ages to being again!

But I stumble over several uncertainties.

First of all: are "dewa" and "ja" always interchangeable. Could you say "dewa mata" for example? Sounds weird to me.
On the other hand "jōzu ja arimasen" sounds not too nice if you ask me. "jōzu dewa arimasen" sounds a bit prettier and less of a tongue-breaker.

Secondly: I'm learning that "you understand well" would be "yoku wakarimasu", while "you speak well" would be "jōzu ni hanashimasu". Is it really carved in stone like that? Or can you also say "jōzu ni wakarimasu" and "yoku hanashimasu".

Third: I know and understand that the "g" sound be more or less pronounced as an "ng". But when I see movies or YT clips or listen to Japanese lessons, I think I hear women pronouncing it more like an "ng" and men pronouncing it more like a "g" (like in the English word "give"). Is that a coincidence? Or is that just my imagination? Or is it really like that?

Fourth: what is the actual difference between the particles "ga" and "wa"?

[community.japanese]

-san
konnichiwa! It's great you started doing some Japanese exercises!

1.
I would say 'dewa' and 'ja' are not very interchangeable because the politeness is different.
Meaning is pretty much same, but you need to choose one over the other according to the politeness level you're using to communicate with the other(s). So, 'dewa mata' is absolutely correct and normal to say, and I even use it.

2.
No, you can't swap 'yoku' and 'jōzu'. This is where word-to-word translation does not work and where you have to grasp the meaning
and/or sense of a word and/or a language.
The meaning changes if you say 'yoku hanashimasu' for instance. It then means 'you speak a lot'.

3.
As far as I know, gender difference does not affect the pronunciation. It does, though, vary depending on person and especially
the area they're from. So-called standard Japanese pronunciation would be with 'ng' if 'ga' appears in the middle of a word and
'ga' if a word starts with 'ga' without preceding word.

4.
This is a looooong discussion matter. In a simplest term, 'ga' is the subject-marking particle and 'wa' is the topic-marking particle.
I'd recommend you to focus more on grammar pattern and functions in actual sentences to understand those particles
instead of 'what is the difference' (like a very big picture) because it's not that straightforward.

Hope this helps!

Natsuko (奈津子),
Team JapanesePod101.com