The question addresses mixed constructions in sentences. The original statement is considered a mixed construction, while the other versions either correct this error or maintain it. Correct sentences provide a clearer structure without ambiguity. ;
The question examines mixed constructions, showing that the original statement is mixed due to awkward phrasing. The sentences 'Bacteria that exist in the mouth...' and 'Bacteria in the mouth...' are correct, while 'One reason why cavities...' remains a mixed construction. The correct sentences provide clarity and a straightforward cause-and-effect relationship.
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