I tried to reach him, but the line was engaged.

我试过联系他，但电话占线。

《柯林斯英汉双解大词典》

The line isn't engaged.

这线路不占线。

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British retailer Woolworths has produced 100,000 souvenirs ready to be deployed to stores if Prince William, second in line to the throne, and his girlfriend Kate Middleton get engaged.

日前，英国杂货零售商伍尔沃思公司未雨绸缪，提前为英国王位第二继承人威廉王子和其女友凯特·米德尔顿的订婚仪式设计制造了10万件纪念品，以便在婚约宣布后的第一时间上架销售。

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With an engaged following, you create an endless line of opportunities to recoup your investment in the advertising every time you publish new content.

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Just for one single battle preparations have often to be made for decades on end and the plans deeply laid, and while only some thousands fight in the front line there are behind them millions engaged in various tasks which, though small themselves, contribute directly to the supreme effort.

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Engaged factory workers pull the chain to stop the entire line when they notice a defect.

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