他用拨火棍打我的肩膀。He swiped me across the shoulder with the poker.他及时低下头，躲过了拨火棍的击打。He ducked in time to save his head from a blow from the poker.他俯下身,用拨火棍拨了一下火.He bent down and stirred the fire a poker....
护照过期是无效的.A passport that is out of date is invalid.今天宇航员将会做最后一次尝试，力图把一颗通信卫星从无效的轨道上抢救下来。Astronauts will make a final attempt today to rescue a communications satellite from its useless orbit.此外，他们还声称任何这样的干预都是完全无效的。Further...