Is the object uniquely determined when using は in the following sentences?


> 卵は私が食べた。Speaking of the egg, I ate.

Is what I ate the egg? Is it possible that I ate something other than the egg?




> 「[玉子]{たまご} **は** [私]{わたし}が[食]{た}べた。」

If this were the only sentence given, all we know **for sure** would be that
**_the speaker ate the egg_**.

The sentence says nothing about whether or not the speaker ate something else
besides the egg. Maybe he did and maybe he did not. The speaker just did not
mention it.

One could add another sentence using 「も」 as in:

> 「ハム **も** 私が食べた。」

to say one ate the ham as well.

Finally, if a John ate the bread, one could add the sentence:

> 「でも、パン **は** ジョンが食べた。」

or

> 「でも、パン **を** 食べたの **は** ジョンだ（or だった）。」

