题干
When he was unknown ________the young people, he served ________ a singer at a bar.
A：for; for
B：to; as
C：for; to
D：to; to
答案(点此获取答案解析）
B
When he was unknown ________the young people, he served ________ a singer at a bar.
A：for; for
B：to; as
C：for; to
D：to; to
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