[译] 每次我向他挑战，他都避而不战。
[误] Every time I challenge to him, he gets rid of me.

[正] Every time I challenge him, he gets rid of me.
[注] 动词 challenge 本身已内含“向，对……”的意思，因此不要再加多余的 to。类似的词还有：address (向……讲话，向……致辞）；brief(向……作简要的介绍)；salute(向……敬礼，致敬)等等。