考查文法：G(VT，VN，E，P)

 其中，VT={+，*，(，)，i}，VN={E，T，F}，E为开始符。

 P：E→E+T|T

 T→T*F|P

 F→(E)|i

 F*F+T是该文法的一个句型，在此句型中，(27)是句柄，(28)是该句型的直接推导，(29)该句型的最左推导。

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