It is controversial because some of the explanations are behavioural, and are seen by many as racist slurs.

具有争议是因为有一些解释是行为学上的，被很多人视为种族诽谤。

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Fuhrman, he reminded jurors, lied to them in March, when he denied uttering racist slurs in the past 10 years.

CNN: SEPTEMBER 25

The incident led to Uruguayan Suarez being banned for eight games by the FA, who found him guilty of making racist slurs against Evra.

BBC: Man bailed over FA Cup 'gesture'