make indifferent

"My sister will not be very long, Miss Drummond," he began, in a tone he tried in vain to make indifferent.

For I had long thought that the way to make indifferent things bad, was for good people not to do them.

Around this domain lie the homesteads of Kentucky farmers, who make indifferent monks.

Counts make indifferent guides, but are middling fair waiters.