Please note that coreference between the noun and pronoun is not
possible in the starred sentences (that is, in those sentences, the
pronoun cannot be interpreted as referring to the same individual as the
name in the sentence):

The sentences below are the samples:

(1-a) When Tom was young, he was rich.
(1-b) When he was young, Tom was rich.
(1-c) He was rich when Tom was young.  *** he does not equal 'Tom'
(1-d) Tom was rich when he was young.

(2-a) I like Jack because he is handsome.
(2-b) I like him because Jack is handsome. *** 'him' is not 'Jack'
(2-c) Because he is handsome, I like jack.
(2-d) Because Jack is handsome, I like him.

(3-a) It is not until you lose health that you realize its importance.
(3-b) It is not until you lose it that you realize the importance of
health.

(4-a) After you lose your membership in it, the younger generation seems
pretty bad.
(4-b) After you lose your membership in the younger generation, it seems
pretty bad.

(5-a) Tom said that he had not murdered his wife.
(5-b) He said that Tom had not murdered his wife. *** 'he' is not 'Tom'

These cases are examples of a phenomenon quite famous in syntactic
theory; people have been trying to develop an adequate account of why
coreference is blocked in such cases for a long time now; many people
believe that there are answers. I don't know what the current set of
rules is. But it's important to note that coreference is blocked in
these cases;  you can't always alternate the pronoun/noun order and
preserve the meaning of the sentence. Keywords in the syntax literature
would be 'C-command', 'coreference', 'constraints on coreference', and
'binding'. Be prepared for full-bore syntactic theory; it might be
helpful to consult an introduction-to-generative-syntax text for a
discussion accessible to someone with little/no linguistics training. I
believe a lot of intro books would discuss this issue, since it is so famous.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Johanna Rubba   Assistant Professor, Linguistics
English Department, California Polytechnic State University
One Grand Avenue  • San Luis Obispo, CA 93407
Tel. (805)-756-2184  •  Fax: (805)-756-6374 • Dept. Phone.  756-259
• E-mail: [log in to unmask] •  Home page: http://www.calpoly.edu/~jrubba
                                       **
"Understanding is a lot like sex; it's got a practical purpose,
but that's not why people do it normally"  -            Frank  Oppenheimer
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