  Let $w \in F_2$ be a word and let $m$ and $n$ be two positive integers. We
say that a finite group $G$ has the $w_{m,n}$-property if however a set $M$ of
$m$ elements and a set $N$ of $n$ elements of the group is chosen, there exist
at least one element of $x \in M$ and at least one element of $y \in M$ such
that $w(x,y)=1.$ Assume that there exists a constant $\gamma < 1$ such that
whenever $w$ is not an identity in a finite group $X$, then the probability
that $w(x_1,x_2)=1$ in $X$ is at most $\gamma.$ If $m\leq n$ and $G$ satisfies
the $w_{m,n}$-property, then either $w$ is an identity in $G$ or $|G|$ is
bounded in terms of $\gamma, m$ and $n$. We apply this result to the 2-Engel
word.
