Noun + Preposition Combinations

Mistake 1: reason of

"What is the reason of the delay?"

Correct: "What is the reason FOR the delay?"

Mistake 2: solution for

"We need a solution for this problem."

Correct: "We need a solution TO this problem."

Mistake 3: effect of

"The effect of the medicine was quick."

Correct: "The effect ON the patient was quick."

Mistake 4: key of success

"Practice is the key of success."

Correct: "Practice is the key TO success."

Historical convention

Many combinations come from Latin, French, or Old English roots. "Solution to" mirrors the Latin "solutio ad", while "fear of" follows the Old English genitive pattern.

Semantic grouping

Some prepositions cluster by meaning: nouns expressing desire or purpose often take "for" (need for, demand for), while nouns showing direction take "to" (approach to, reaction to).

Adjective-noun parallels

Many nouns take the same preposition as their related adjective: interested in → interest in, responsible for → responsibility for. But not always: proud of → pride in.