You’re sweating heavily. You look tired ( ) running.

　　A. of

　　B. at

　　C. by

　　D. with

　　【答案】D。be tired with sth是固定搭配，意为：因…感到疲倦。Look和be都是系动词，用法是相通的。所以这里可举一反三，用be tired with sth这个搭配。