This thread revolves around pronoun ambiguity and the placement of the adverb ‘originally’
1. they originally seemed --- The pronoun ‘they appears in two junctures, the first one referring to the researchers, and the second one referring to the plastics ( thereby their disintegration time) . The second one cannot logically refer to researches since it absurd to expect researchers to disintegrate.
2. they seemed originally ---- same problem as in A.
3. it seemed that they would originally ---- ‘It’ holds the place value. But the placement of the adverb is a problem in this choice. It gives a feeling that the plastics originally dissolved quickly, while now they are taking more time. This is wrong perception.
4. it originally seemed--- The adverb placement is ok; but the pronoun it now refers to the plural plastics.
5. it originally seemed they would--- may be this is the solution with it taking its place holder value and the adverb originally modifying the disintegration time and the plural pronoun they modifying the plastics.
What is odd about this thread is that, most of the pointers are more of intuitions and personal perceptions.
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