• Perfect Aspect
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○○○ Pluto ⪢⪢
Pluto had been considered the ninth planet until 2006 when it was renamed a dwarf planet.
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Pillow English Listening

• Present Perfect
If the result of the past action continues now, we use present perfect.
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• Present Perfect
Scientists say they have found evidence of a giant planet in the solar system. There have only been two true planets discovered since ancient times. Planets have been predicted before and then were not found.
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• Present Perfect or Past Simple 1
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• Present Perfect or Past Simple 2
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