1. I arrived at the hospital at 7 p.m.

2. I arrived at the hospital at around 7 p.m.

3. I arrived at the hospital around 7 p.m.
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Can we use all the expressions?
Can we use 'at around' as in Sentence 3?

Yes to both questions.

1. I arrived at the hospital at 7 p.m.

2. I arrived at the hospital at around 7 p.m.

3. I arrived at the hospital around 7 p.m.
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Can we use all the expressions?
Can we use 'at around' as in "Sentence 2"? Thank you. You mean all are grammatical?

The word "at" means right at that hour, so "at 7 p.m." means it! The word "around" means close to that hour, maybe a few minutes before or after.

While "at around" is not really incorrect, it is rather self-contradictory!! I would use either "at" or "around," but you can use any of the three expressions.

Yes, all three expressions can be used to indicate the time at which you arrived at the hospital. However, there are slight differences in their usage:

1. "I arrived at the hospital at 7 p.m.": This sentence specifies the exact time of your arrival at the hospital. It suggests that you arrived precisely at 7 p.m.

2. "I arrived at the hospital at around 7 p.m.": In this sentence, the word "around" indicates an approximate time. It implies that you arrived sometime close to but not exactly at 7 p.m. It gives a bit of flexibility to the exact time.

3. "I arrived at the hospital around 7 p.m.": Similar to the previous sentence, this expression also suggests an approximate time. The word "around" means that you arrived sometime near or about 7 p.m. It also allows for some leeway in the exact time.

So, while all three expressions convey a similar meaning, the use of "at around" in Sentence 3 may sound slightly less precise compared to the other two options.