The switches close the contacts and complete the circuit.

这些开关可接通形成闭合电路。

《牛津词典》

The switch closes the contacts and complete the circuit.

这个开关可使接触器接通电流形成回路。

youdao

That is the minimum number necessary to complete the circuit.

这是完善循环的最低限度人数。

youdao

The whole device, together with a second electrode (known as a reference) to complete the circuit, is then mounted on a stick.

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He is hoping to complete the marathon circuit in about fourand-a-half hours.

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On Oct. 21, the promoters organized a christening ceremony complete with rides around the circuit courtesy of Mario Andretti, the only living American F1 champion.

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