appoint v. /assign v.
appoint的意思是“任命，指派，委任”，后多跟职位一类的名词;
assign的相关意思是“分配，分派，指定”，后多跟具体的工作。
例：They appointed him Minister of Education.
他们任命他为教育部长。
She was appointed to the Chairmanship of the Committee.
她被任命为委员会的主席。
The problem was assigned to a commission.
这项任务交给了一个特别委员会去处理。
I assign you to wash the dishes.
我分配你去洗盘子。