A prepositional phrase is a series of words beginning with a preposition and providing additional information in a sentence that pertains to position (hence the word preposition) or relationship; the phrase “with a preposition” is itself a prepositional phrase.
Though such phrases are not inherently undesirable, they are often easily avoidable contributors to compositional clutter. This post lists and describes five strategies for eliminating prepositional phrases by omission or alteration.
1. Use active voice. A prepositional phrase beginning with by often signals an opportunity to convert a passively constructed sentence into active voice (and render it more concise), as when, “The action was seen by observers as nothing more than a delaying tactic,” is revised to, “Observers saw the action as nothing more than a delaying tactic.”