do动词的完成时态
英语中的完成时态有现在完成时。即助动词have或has+动词的过去分词done.如:I have done the work. 完成时态还有过去完成时。就是had +done。通常称为过去的过去。如The building had finished last year.还有将来完成时由will+have+done表示。如:By this time tomorrow，she will have arrived in Xuzhou.
英语中的完成时态有现在完成时。即助动词have或has+动词的过去分词done.如:I have done the work. 完成时态还有过去完成时。就是had +done。通常称为过去的过去。如The building had finished last year.还有将来完成时由will+have+done表示。如:By this time tomorrow，she will have arrived in Xuzhou.
