drifting object

基本解释

Presently a dark object was seen in the river, drifting towards us.
不多一会儿，只见河上有个黑不溜秋的玩意儿在向我们漂来。
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The top three causes of the accidental injury are: road accident injury (43.4%), drifting-down injury (31.7%) and the bruise injury caused by heavy object (12.8%).
造成意外伤害的原因前三位是交通伤（43.4%）、跌落伤（31.7%）、重物砸伤（12.8%）。
An unmanned free balloon shall refer to a freely drifting inflatable object which is driven with no power, is piloted by nobody, is lighter than air, and whose gross mass is more than 4 kilograms.
无人驾驶自由气球，是指无动力驱动、无人操纵、轻于空气、总质量大于4千克自由漂移的充气物体。