"But he is a man, not a machine."

Translation: Ale on je muž, ne stroj.

[diceopolis]

It didn't accept "Ale to je muž, NENÍ stroj" as correct. Why "ne" but not "není". I understand using je and then není is redundant, but shouldn't it be correct?

[BoneheadBass]

I think "není" may be rejected because it would make the sentence more like "But he is a man, HE IS not a machine," while the original is "But he is a man, not a machine."

So the Czech and English versions match up better using "ne" instead of "neni" -- "But he is a man, NOT a machine."