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at intervals (of) at home and abroad at firstgaze at fever pitch at fault at ease march

at intervals (of)
生词本

1. She began to menstruate regularly at 13 at intervals of 28～32 days with slight dysmenorrheal.
她于13岁开始有正常的月经，周期为28～32天，有轻度的月经痛。

来自《简明英汉词典》

2. These cars are put at intervals of three meters.
这些车每隔三米放一辆。

来自《简明英汉词典》