TAKOBOTO

'ha (wa)' used to indicate contrast
I don't eat /meat/ (but I do eat fish).

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わたしはにくはたべない。

I don't eat / meat / . (but I eat fish)

「をみせて！」「しんぱいはいらない。いきてはいる、いきて。」

"Show me Serena!" "No need to worry. She's / alive / . Alive (but _not_ well)."

いや、でもやきゅうをみにいくのはすきだけどね。

No, but I like + going to baseball.

わたしは、たしざんはすきだけど、ひきざんはきらいだ。

I like + addition but + subtraction.

かれはしゃんはいですんでいたので、せんそうはかれとはまったくかんけいのないところでおこなわれていた．

Because he was living in Shang-hai, the war was being fought (lit. performed) in places that did not have a connection with him at all.

さかなはたべますが、にくはたべません。さかなはたべますが、にくはたべません。

I eat + fish, but I don't eat meat.

The 'normal' negative sentence would be 私は肉を食べない。'I don't eat fish'.
With the object marker を overridden by は this implies that not eating meat is in contrast to eating something else (for example fish).
Note: When Japanese refer to meat (肉) they generally would not understand that as including fish (魚).

Amatuka

This contrastative は can fit in places that you might not expect. Take 生きている '(she's) alive.' vs. 生きてはいる '(she's) alive (but not well).'.

Amatuka

P.S. How's the Hero / Villain / Hostage example?

Amatuka

Very helpful :)

Kana-chan

In your comment, you said "私は肉を食べない。'I don't eat fish'”, but obviously you meant to say 'I don't eat meat'. I also liked the hostage example! :-)

khyron