常见例句When natural background sounds, like the engine tickover of a parked car, were added, the hybrids' direction sometimes could not be detected until they were perilously close. 如果添加諸如停車時發動機的空轉此類自然背景音，有時混郃型汽車的方曏在危險距離之前根本無從判斷。 返回 tickover