group reorganization

a group reorganization (or restructuring) is any of the following:
(a) the transfer of shares in a subsidiary from one group entity to another
(b) the addition of a new parent entity to a group
(c) the transfer of shares in one or more subsidiaries of a group to a new entity that is not a group entity but whose shareholders are the same as those of the group,s parent
(d) the combination into a group of two or more companies that before the combination had the same shareholders
(e) the acquisition of the shares of another entity that itself then issues sufficient shares so that the acquired entity has control of the combined entity
Sir plz cannot understand this what is the meaning of reorganization please help me i will be thankful to you