10 unthinking

unthinking
adj
said, done, etc without proper consideration; thoughtless 考虑不周的; 未经思考的
    unthinking remarks, criticisms 失慎的言语、 批评
    Unthinking, he threw his lighted match into the waste-paper basket. 他想也没想就把燃著的火柴扔进了废纸篓里了.