When is "wa" written as は?

[gaijin_girl]

I've been having trouble figuring out when wa is written as は instead of わ. If there is a list somewhere explaining the differences I'd really love to have the link. :)
Thanks in advance!

[undrentide]

I've been having trouble figuring out when wa is written as は instead of わ. If there is a list somewhere explaining the differences I'd really love to have the link. :)
Thanks in advance!

Well, it is a bit different - when used as a particle, は is pronoucned わ.
(The particle has never been わ.)
Otherwise は is pronounced as it is - は (ha).

[hideway]

You also have the case of konnichiwa and konbanwa. Both written with 'ha' but read as 'wa'.

ps: Yeek, For some reason it is starting to feel wierd to write any romaji at all. Is this normal?

[Skuu]

The above posters are right but I'll add something to make it clearer if needed.
は in this context shows the topic of a sentence, it goes after the topic, hence why the particle is called a 'topic-marker'.
sakana は oishii desu.
Fish is tasty.

A good way for beginners to think of it, is to see it as 'as for...'
(as for) fish, it's tasty.

The は in konnichiwa and konbanwa are just a figure of speech kinda like 'howabout that weather', don't have to worry about the grammar there.

Apart from that, は usually just means the sound HA.

Hope that helped.

[Mikawa Ossan]

Actually, KONBANWA and KONNICHIWA are probably shortened versions of a longer original sentence, and therefore are just the topic of the original sentence.

SAYOUNARA is actually a sentence fragment, after all, too. TADAIMA spoken when arriving at home is shortened "TADAIMA KAERIMASHITA".

OHAYOU GOZAIMASU is a complete thought, but litterally, it only actually means "it's early".

[Skuu]

Oh that's interesting. Good point. Although because they're used as phrases now, the は is often written as HA in romaji. You can see it either way I believe. Although in proper Japanese writing it will always be は.

Here's some more examples of は's usage as a particle (topic-marker).

kyou は　samui desu. Today is cold.
ano basu は hayai desu. That bus is fast.
neko は　kawaii desu. Cats are cute.

There's no English equivalent, so just remember that you put it after the topic of the sentence (today, bus, cat; whatever you're talking about), then you proceed to describe it.

you は (as for today), samui desu, it's cold.

[NattyBumppo]

you は (as for today), samui desu, it's cold.
This confused me a lot until I realized that you meant "kyou."

[Skuu]

Rofl, sorry about that. :p

[EvilCowSlayer]

わ can also be a particle, but it means something completely different from は as a particle.