Usages of по
Её любимые ученики ещё маленькие: им по семь-восемь лет.
Her favorite students are still small: they are about seven or eight years old.
Мы гуляем по парку вечером.
We walk around the park in the evening.
Если у Вас есть какой-либо вопрос по возврату, оператор ответит до вечера.
If you have any question about the return, the operator will answer by evening.
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