1. Wangfujing Street in Beijing Street is crowded day and night.
2. Wangfujing Street in Beijing Street is crowded night and day.
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Are both grammatical? Is only #1 right?
How can you have a street in a street?
Both sentences are grammatically correct, but they have slightly different word orders and emphasize different parts of the day.
1. "Wangfujing Street in Beijing Street is crowded **day and night**."
This sentence emphasizes that the street is crowded consistently throughout the entire day and night.
2. "Wangfujing Street in Beijing Street is crowded **night and day**."
This sentence emphasizes that the street is crowded primarily during the night and also during the day.
Therefore, both sentences are acceptable, but the choice between using "day and night" or "night and day" depends on which aspect of the street's crowding you want to highlight.