野牛语法偶尔通过，偶尔失败

我第一次广泛使用Bison语法。我已经设置好了语法，还有一个用来关联结果的小测试套件。

偶尔，测试套件会通过：

Reducing stack by rule 101 (line 613):
   $1 = nterm mathenv ()
-> $$ = nterm closedTerm ()
Stack now 0 5 3
Entering state 120
Reading a token: Next token is token ENDMATH ()
Reducing stack by rule 28 (line 517):
   $1 = nterm closedTerm ()
-> $$ = nterm compoundTerm ()
Stack now 0 5 3
Entering state 119
Reducing stack by rule 12 (line 333):
   $1 = nterm compoundTerm ()
-> $$ = nterm compoundTermList ()
Stack now 0 5 3
Entering state 198
Next token is token ENDMATH ()
Shifting token ENDMATH ()
Entering state 325
... continues to completion ...

偶尔不会：

Reducing stack by rule 101 (line 613):
   $1 = nterm mathenv ()
-> $$ = nterm closedTerm ()
Stack now 0 5 3
Entering state 120
Reading a token: Next token is token MN ()
Reducing stack by rule 28 (line 517):
   $1 = nterm closedTerm ()
-> $$ = nterm compoundTerm ()
Stack now 0 5 3
Entering state 119
Reducing stack by rule 12 (line 333):
   $1 = nterm compoundTerm ()
-> $$ = nterm compoundTermList ()
Stack now 0 5 3
Entering state 198
Next token is token MN ()
Shifting token MN ()
Entering state 11
... errors eventually ...
Now at end of input.
Line: 9 Error: syntax error at token 

ENDMATH是要转移到的正确标记，但有时MN是确定的。每当我进行测试时，我都会得到不一致的结果。这种"随机"的歧义是正常的吗？是什么原因造成的？我应该定义一些%precedence规则吗？

在y.output的顶部，我确实看到了一些状态冲突，比如

State 0 conflicts: 3 shift/reduce
State 120 conflicts: 2 shift/reduce
State 127 conflicts: 2 shift/reduce
State 129 conflicts: 2 shift/reduce
State 154 conflicts: 1 shift/reduce
State 207 conflicts: 3 shift/reduce
State 265 conflicts: 109 shift/reduce
State 266 conflicts: 109 shift/reduce
State 267 conflicts: 109 shift/reduce
State 268 conflicts: 109 shift/reduce
State 269 conflicts: 109 shift/reduce
State 342 conflicts: 2 shift/reduce
State 390 conflicts: 109 shift/reduce
State 391 conflicts: 109 shift/reduce
State 396 conflicts: 1 shift/reduce
State 397 conflicts: 1 shift/reduce

消除所有这些冲突是否可取？注意，状态120被列为具有冲突，并且是正好在该随机错误发生之前的状态。