对运动前后的身体状况进行测量前,一定要____,否则对运动前后身体变化的比较就不够准确。
You had better _________ wine because you have to drive back home.
如图,在▱ABCD中,E为CD上一点,连接AE、BD,且AE、BD交于点F,S△DEF:S△ABF=4:25,则DE:EC=( )