We were having so much fun the _______, and before we knew it, it was time to go home.
A. time flies
B. time flying
C. time flew
D. time flewed
查看答案
Why do we have an extra day every four years, known as a ‘leap year’?
How much shorter is 2021 calculated to be?
True or False?A leap second might have to be subtracted from time for the firsttime ever.
What are the most important devices for accurate timekeeping?
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