English for Today by Ganiu Abisoye Bamgbose (Dr GAB)
Do you FROWN ON or you FROWN AT?
He ~frowned on~ her sister excitingly (nonstandard).
He *frowned at* her sister excitingly (standard).
When someone frowns, their eyebrows become drawn together, because they are annoyed, worried, or puzzled, or because they are concentrating.
My students know I ~frown at~ lateness (nonstandard).
My students know I *frown on* lateness (standard).
My students know I *frown upon* lateness (standard).
You frown on or upon something/habit when you dislike the thing/habit.
GAB
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