Preposition rule

• Preposition Rule

There is one very simple rule about prepositions. And, unlike most rules, this rule has no exceptions.

Rule
A preposition is followed by a "noun". It is never followed by a verb.

By "noun" we include:

• noun (dog, money, love)
• proper noun (name) (Bangkok, Mary)
• pronoun (you, him, us)
• noun group (my first job)
• gerund (swimming)

A preposition cannot be followed by a verb. If we want to follow a preposition by a verb, we must use the "-ing" form which is really a gerund or verb in noun form.

Subject + verb preposition "noun" The food is on the table.She lives in Japan.Tara is looking for you.The letter is under your blue book.Pascal is usedtoEnglish people.She isn't used to working.I ate before coming.

Source:  http://www.englishclub.com/grammar/prepositions.htm