“take”表示把什么〈东西，物品)随身带走,“bring”表示把什么(东西，物品)随身带来。
所以take an umbrella 是正确的，表示随身带走一把伞。
bring an umbrella也是正确的，表示随身带来一把伞。
主要取决于语境。如，
Take an umbrella just in case.
带把雨伞以防下雨。
Please bring me an umbrella.
请给我带把雨伞。
是take an umbrella 还是 bring an umbrella？就看对于说话者来说是“带来”还是“带走”。
take 和bring的意思都是 “带……”。相对于说话者来说，take是“带走”，bring是“带来”.
例句：
It is cloudy.You had better take an umbrella with you when you leave.
The teacher said,“ It is going to rain next Saturday, don't forget to bring an umbrella with you when you come to school next week.”
