In compiling a grammatical text we were faced with the problem of finding numerous example sentences to illustrate semantic differences. We had some problems with finding a good example for contrastive adjectives. Eventually we settled on the sentence: These are biological not chemical weapons. Our first example was: They hired a criminal not a corporate lawyer. Unfortunately, non-linguists had a hard time realizing that we meant "criminal" to be an adjective and not a noun ...
(From the "Rest" of RHF)