下面几句是我收集的不定式加完成时的句子。(可能还不全)。 我也对这个问题不懂，看看大家能不能从下面的句子里看出点道道来。
(1) A huge flying reptile that died out with the dinosaurs some 65 million years ago, the Quetzalcoatlus had a wingspan of 36 feet, and
it is blieved to have been the largest flying creature the world has even seen.
(2) The fear of rabies is well founded; few people
are known to have recovered from the disease once the clinical sysmptoms have appreared.
(3) Geologiests believe that the Bering land bridge, over which human beings
are thought to have first entered the Americans, disappeared abt 14,000 years ago when massive glaciers melted and caused the sea level to rise several hundred feet worldwide.
(4) In June, 1981, six teenagers in the village of Medjugorje, Yuugoslavia,
claimed to have had visions of the Virgin Mary, who they say has continued to appear to them over the ensuing years.
(5) The domestication of the camel,
thought by some scholars to have occurred around the twelfth centry B. C, was the key to the development of the spice trade in the ancient world.
(6) The distinctive hereditary tartans
alleged to have been worn since antiquity by memebers of the Higland clans were in fact designed by Scottish woolen manufactures in the eighteenth and nineteenth centruies.
(7) For some birds the sense of smell appears to play a role in navigation, since pigeons with surgically removed alfactory nerves
have been found to have increased difficulty in homing.
还有一些是不能加完成时的，比如楼主那句，和下面这句。
The western world's love affair with chocolate is well-documented; few people
have been known to taste it for the first time without requesting more。
大家都来讨论吧，让我们搞懂这个问题。众人拾柴火焰高哪！
-- by 会员 dansy (2004/1/6 10:32:00)
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发表于 2011-8-19 15:34:42
