compiler construction - Ambiguous grammar in parse phase -

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i want build compiler own language, wrote grammar , finished lexer phase question in parse phase part of ebnf grammer 

       statement      →     block | assignment | callstatement | declaration |                              inputstatement |outputstatement | ifstatement | whilestatement         callstatement  →     identifier { /[expression/] }  {. identifier } /( arguments /)         lefthand       →     identifier { /[expression/] }  {. identifier { /[expression/] } }

i use recursive descent parser method , problem distinguish between callstatement , lefthand ,how should solve ,i apologize if can't explain idea :(


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