HBV基因组结构中,S区S基因编码HBsAg,前C区编码HBcAg,PHSA-R由前S1区编码。
参考答案:错
Tom, together with his classmates, ______ because of _______ the school rules.
A.was punished, obeying
B.were punished, obeying
C.was punished, breaking
D.were punished, breaking
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