Re passive vs. active past participles: given that passive sentences are
relatively rare in most genres of English, it is probably true that most
occurrences of the past participle verb form are not passive.

I think what Dick Veit is getting at is that when a past participle is
used as a modifier (half-eaten cookies) rather than as part of a verb
phrase (we have eaten the cookies), it is most often passive. I think he
is thinking of occurrences of participles in participial phrases -- 'the
investors, _discouraged_ by the wildly fluctuating market, retreated to
blue-chip mutual funds'. But what about cases like  'a fallen tree'?
'The tree fell', 'The tree has fallen' aren't passives.

Here again the category/function distinction is important. 'Participle'
is the category that the form of the verb belongs to -- it's one of a
verb's 'principal parts'; it has various functions -- as adjective-like
modifier, as part of a tense/aspect construction such as present
perfect, etc.

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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
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"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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