You should keep your money in a safe place.Have you ever told a friend to "drive safe"?

Eighteenth-century grammarians didn't even identify flat adverbs as adverbs; they considered them adjectives and the adverbial use to be a mistake.A safe driver; He's a very fast driver but he's safe enough.From, cambridge English Corpus, these results suggest that twin studies of substance use are unlikely to be biased and may be safely extrapolated to more typical non-twin family relationships.

Not likely to cause harm.The missing child has been found safe and well.From, cambridge English Corpus, it is the septal component adjacent to the obtuse margin which can safely be resected to enlarge the defect.