relative clauses - a way that most people think {is / it is} wrong

I was reading definition/meaning of the word "perverse" in Oxford Dictionary, came across :

showing deliberate determination to behave in a way that most people think is wrong, unacceptable or unreasonable

Shouldn't it be :

showing deliberate determination to behave in a way that most people think it is wrong, unacceptable or unreasonable

Answer

Your it is unncessary.

You understand correctly that there is an empty 'slot' in the sentence—the subject of the clause is wrong &c.

There are two ways of looking at what's going on:

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  In traditional grammar the that is understood to be a "relative pronoun" which 'stands for' a "referent" or "antecedent", way, and acts as the displaced subject of is wrong &c

  
  



• 
  

  Many contemporary grammars call the that a "relativizer", a sort of variable which points backward toward the referent, the variable's 'value', and forward toward an empty slot ("gap" or "trace"); it instructs the hearer or reader to find the gap and fill it with the value.

  
  

The two analyses amount to pretty much the same thing: that empty slot is a feature, not a bug; StackExchange would tag it by-design.

It is not ungrammatical to fill the gap with it as you do; this happens frequently in speech. (Grammarians call it a resumptive pronoun, one which 'resumes' mention of the referent.) However, it is redundant, and is deprecated in writing.