They signify that, while it is up to the State intending to attach a reservation to its expression of consent to be bound to indicate how it means to modify its participation in the treaty, this formulation is not sufficient of itself.
意思是虽然打算对表示同意接受约束附加保留的国家有义务说明如何修改参加条约的方式 ，但是，提具保留本身并不够。