If his parents are convinced the fact that his son always focuses his mind his s
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If his parents are convinced ______ the fact that his son always focuses his mind _______his study.
A. of; on B. of; at C. by; to D. on; at
试题答案
A
解析:
be convinced of sth “确信；坚信某事。”focus one’s mind/attention on sth.将注意力集中于某事物。