可用句柄来对句子进行归约 句型归约规则 abbcde(2)A→b aBode(3)A→Ab aAcde (4)B>d aAcBe(1)s→ aAcBe s可用句柄来对句子进行归约 句型 归约规则 abbcde (2) A → b aAbcde (3) A → Ab aAcde (4) B → d aAcBe (1) S → aAcBe S