mistake
take sth by mistake 错拿.mistake加不加s呢by mistake 是习语， 错误地1. Be careful that you don't set the fireworks off by mistake. 当心点，别弄错了引起那些爆竹爆炸。 来自《简明英汉词典》2. Excuse my taking your umbrella by mistake. 请原谅我错拿了你的伞。 来自《简明英汉词典》就是固定句型呗、