the position of "by someone" in the passive

English as a Second Language English Vocabulary, Grammar and Idioms
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  1. He was bitten by a dog in the park.
  2. He was bitten in the park by a dog.
  3. The eggs were put in the refrigerator by him.
  4. The eggs were put by him in the refrigerator.
  5. The movie has been seen many times by him.
  6. The movie has been seen by him many times.
  7. He was asked to clean this room by his mom.
  8. He was asked by his mom to clean this room.
  9. David was killed by his neighbor yesterday.
  10. David was killed yesterday by his neighbor.
    Which of the above sentences is NOT acceptable?
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The problem is that many such passive constructs are unacceptable by nature; they often are awkward and little used.

  1. He was bitten by a dog in the park.-- OK
  2. He was bitten in the park by a dog.-- OK
    3/4-- Too awkward to live: He put the eggs in the fridge. Pronouns by their unstressed nature tend to be uncalled for in this structure.
    5/6-- Too awkward to live: He’s seen the movie many times[/i].
  3. He was asked to clean this room by his mom.– OK
  4. He was asked by his mom to clean this room. – OK
  5. David was killed by his neighbor yesterday.– OK
  6. David was killed yesterday by his neighbor. – OK

The only caveat in adverb placement is that confusion should not reign, as in: He was bitten by the dog in the pants.
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