来自顾建华的问题
thebrownhorsecan____1___veryfast.lookit's____2____withadoga.runrunningb.runs,runningc.run,run
thebrownhorsecan____1___veryfast.lookit's____2____withadoga.runrunningb.runs,running
c.run,run


thebrownhorsecan____1___veryfast.lookit's____2____withadoga.runrunningb.runs,runningc.run,run
thebrownhorsecan____1___veryfast.lookit's____2____withadoga.runrunningb.runs,running
c.run,run
a.runrunning
can后面必须跟动词原形
isrunning=现在进行时