English for Today by Ganiu Abisoye Bamgbose (Dr GAB)
USING PREPOSITIONS WITH LOCATIONS AND PLACE
They live ~at~ the outskirts of Lagos (nonstandard).
They live *in* the outskirts of Lagos (standard).
They live *on* the outskirts of Lagos (standard).
“Outskirts” is used with “in” and “on”. Note too that “outskirts” ends in “s”, not “t”.
Some of them live ~at~ the island (nonstandard).
Some of them live *on* the island (standard).
The preposition “on” is used with “mainland”, “island” and “floor”:
He does his banking ~at~ the mainland (nonstandard).
He does his banking *on* the mainland (standard).
Her office is ~at~ the first floor (nonstandard).
Her office is *on* the first floor (standard).
GAB
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