The experiment having been done, the students left the laboratory.
做完这个实验后,学生们就离开了实验室.
The business having been promised must be done.
答应别人的事一定要做到.
John has been aware of having done something wrong.
约翰已意识到自己做错了事情.
said or done without having been planned or written in advance.
说话做事没有事先计划或预先写好的.
