Question 4: ………… only in the Andes, the plant is used by local people to treat skin diseases.
When reducing two clauses with the same subject “the plant”, the reduced clause is reduced to the form:
V-ing when it means active
Ved/ V3 when it means passive
having PP when the action is shortened means active and happens before the other action
find – found – found: find, find
found – founded – founded: established
Full sentence: The plant is found only in the Andes, it is used by local people to treat skin diseases.
Only found in the Andes, the plant is used by locals to treat skin diseases.
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