prefer - prefers - preferring - preferred; believe - believes - believing - believed;
agree - agrees - agreeing - agreed; speak - speaks - speaking - spoke;
sit - sits - sitting - sat; die - dies - dying - died;
ask - asks - asking - asked; read - reads -reading -read.
方便的时间 at your convince; when it is convenient for you;
许多车辆 many vehicles,a lot of cars,a lot of traffic