[] to get on a plane, bus, train, etc. 登上（飞机、公共汽车、火车等）◆The passengers are waiting to board. 乘客正在等候登机。
[] be boardingwhen a plane or ship is boarding, it is ready for passengers to get on 开始登机（或上船等）◆Flight BA193 to Paris is now boarding at gate 37. 请乘坐 BA193 航班飞往巴黎的乘客现在从 37 号登机口登机。