His careless, swinging stride became a heavy, slackening tramp, and at last he halted altogether.

So careless were owners in preventing the promiscuous mingling of alien breeds that it is little short of surprising so many of our canine types have been preserved in their integrity.

Careless is a common adjective, compared by means of the adverbs; careless, more careless, most careless; or, careless, less careless, least careless.

We lived a life as careless as birds.