issue an order in the morning (/at dawn) and rescind it in the evening (/at dusk)—inconstant in policy;make frequent changes in one’s opinions (/policies);make unpredictable changes in policy ❍ 他们经常是～，出尔反尔。They made frequent changes in their policies and often went back on their own words.
朝令夕改zhao ling xi gai
issue an order at dawn and change it at dusk
朝令夕改
issue an order in the morning and rescind it in the evening—make policy changes at will
朝令夕改zhāo lìnɡ xī ɡǎi
早上下的命令，晚上就改掉了。形容政策或法令时常更改，使人无所适从。make up predictable changes in policy, issue an order at dawn and rescind it at dusk