Syntax representation could be considered as the most important phase in developing an NLP system. Most of the grammars used in these systems are phrase structure ones that try to analyze the sentence by decomposing it into sub constituents. There are alternatives to this approach and link grammar as one of them is based on the words instead of constituents, hence called lexical grammar. We are going to assess their ability for Farsi. We do this by starting from the basic relations in Farsi and adding relations to them one by one to give a set of rules for trivial patterns. In each step, link grammar parser on an appropriate test suit tests the validity of the rules.