сначала
см. тж. вначале; начинать сначала; первоначально; предварительно
• With sea water, bromine must first be concentrated before the steaming-out process becomes economically practical.
• The lateral stress decreases initially with time until ...
• At first, these results should be surprising, but a closer look shows that ...
• First we consider fundamental modes and then high-order modes.
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Русско-английский научно-технический словарь
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