S→a|∧|(T)

T→ST '

T' →，ST'|ε

(2) calculating the first episode and post-sequel of each non-terminator;

The first (S)={a, ∧, (}

FIRST(T)={ a，∧，(}

The first (T')={, ε}

Concern = {,#}

FOLLOW(T)={ )}

Follow (T')={ )}

The forecast analysis table is as follows:

A ∧ (), #

SS→aS→∧s →( T)

TT→ Saint → Saint → Saint → Saint

T ' T ' →εT '→，ST '

There are not many entries in the constructed prediction analysis table, so the modified grammar is LL( 1) grammar.