- as to
- Are these words necessary? Usually, a more precise single word will serve better."Eleanor was in doubt as to his meaning" is better expressed "Eleanor was in doubt about his meaning." As to whether is even more useless and wordy. Instead of saying "Sandy expressed concern as to whether it would snow," say "Sandy expressed concern that it would snow." As to where can usually be shortened to where.
Dictionary of problem words and expressions. Harry Shaw. 1975.