The withdrawal of troops from the border is scheduled to begin next month.

withdrawal 是动词 withdraw 的名词形式，由 withdraw（撤回、撤退）加上名词后缀 -al 构成。withdraw 本身由前缀 with-（表示"向后"）和 draw（拉、拖）组成，字面意思是"向后拉"，引申为"撤回、撤退"。 withdrawal 在这里指军队从边境"撤出"的行动或过程。