backrest的复数形式为：backrests...

The truth is, it would be dangerous to sit backrest easy.事实是,如果坐在那里不闻不问, 那才危险.Aluminum - alloy Wheelchair with Fold - down backrest.铝合金高级轮椅背部可折叠.Backrest adjustable as sit, lie, sleep style.靠背可任意调节为坐 、 躺 、 卧状态....

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backrest的音标：backrest的英式发音音标为：['bækrest]backrest的美式发音音标为：['bækˌrɛst]...