The old man kept on studying Chairman Mao’s in his .A. work sixtyB. novels sixtiethC. w

问题补充：

The old man kept on studying Chairman Mao’s in his .

A. work, sixty

B. novels, sixtieth

C. works , sixties

D. books, sixty’s

答案：

A. work, sixty

B. novels, sixtieth

(答案→)C. works , sixties

D. books, sixty’s

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