jack began to learn paintingwhen he was seven 改为现在完成进行时
问题描述：
jack began to learn paintingwhen he was seven 改为现在完成进行时
答
一楼的不是现在完成进行时,那只是简单的现在完成时.
现在完成进行时的框架是：sb have/has been doing sth since...
应该是 Jack has been learning painting since he was seven