My father usually____(go)to work by bus,but he____(drive)his car to work yesterday
用烟煤烧水时,将1kg的水从20℃加热到100℃,燃烧140g的烟煤,则热效率是____ (已知烟煤的热值约为3×107J/kg).
She was injured in the accident and unfortunately she slowly ____(流血)to death.