[cū xīn dà yì]
be negligent; careless; inadvertent; scatter-brain; of a rough heart and big mind; careless and heedless; remiss; thoughtless
I was rather saddened by what he had said and regretted my own carelessness.
我听了他的话心里有点难过， 只怨自己太粗心大意了。
Carelessness deserves the blame for many accidents.
许多事故归咎于粗心大意。