偶然地,臨時地,隨便地
Casually \Cas"u*al*ly\, adv. Without design; accidentally; fortuitously; by chance; occasionally.
casually adv 1: not methodically or according to plan; "he dealt with his course work casually" 2: in an unconcerned manner; "glanced casually at the headlines" [syn: {nonchalantly}]