We finish our lessons at half past four.改为同义句

我觉得这个句子本身的时态有点问题。finish 完成,感觉We finished our lessons at half past four。或者We will finish our lessons at half past four。比较正常。原句的同义句：Our lessons are finished at half past four。Our lessons will be finished at half past four。Our lessons was finished at half past four。