afterthought

[Navi]

Are these sentences correct (the parts that come after the commas are supposed to have been added as afterthoughts):

1-It was the facade, of a tall building.
2-It was an event, of great importance.
3-It was an object, of an undetermined nature.
4-It was an crime, of a premeditated nature.

[Dozy]

The commas look wrong. If you really need to indicate an afterthought, a better way should be sought. For example:

"It was a facade -- the facade of a tall building."
"It was the facade ... of a tall building."

[Yankee]

I agree. That sort of break in thought requires something a bit "stronger" than just a comma.
In your particular examples, just sticking a comma into the middle of a phrase tends to look more like a typo than anything else, Navi.
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