________will the flight arrive at Beijing International Airp

句中arrive at为短暂性动词,
how long对某种状态的持续时间提问,即应搭配延续性动词.所以不能选.
how soon对（从即时起）到将来某个动作发生的时间长短提问,所以可以接短暂性动词.
于是,得出答案为how soon.
How soon will the flight arrive at Beijing International Airport?
飞机还要多久才能到达北京国际机场?
（若要选how long,则句子可以改为
1.How long will the flight fly to Beijing International Airport?Fly为延续性动词.
2.How long does it take to Beijing International Airport?）