单项选择题
A．their friends ask them to do so B．it often rains in England C．they are going to sell them D．they are their favorite things
A．it isn't necessary to know their differences B．there are only a few differences in spoken English C．it will be difficult for others to understand you D．it's hard to remember the differences at the same time
A．Rooster, eraser, color, truck , mail B．Vacation, iii, travelled, licence, center C．Mail, traveled, sick, color, license D．Sick, truck, color, rooster, post