Hot answers tagged prepositions
"At 30% off" would mean that all items are reduced by 30%. "Up to 30%" means that the price reduction may be 30%, or it may be a smaller reduction, such as 25%. Therefore up to is essential to preserve the intended meaning. At may be optional, depending on the context.
There is an advantage in abbreviating some things Valid There is an advantage to abbreviating some things Valid There is an advantage of abbreviating some things Bad, ugly English. But... The advantage of abbreviation is that... or The advantages of abbreviation are... Perfectly acceptable.
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