1. He entered the building.
2. He went in the building.
3. He went into the building.
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Are they all the same in meaning? Which one is frequently used?
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4. Put the milk bottle in the fridge.
5. Put the milk bottle into the fridge.
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Do we have to use 'in' or 'into'? Are both OK? Which one is common?
1, 2, and 3 all mean the same. Probably 3 is the most common.
4 is more common than 5.