  In this article, we present a very general but not ultimate solution of CPV
problem in the standard model. Our study starts from a naturally Hermitian
${\bf M^2}\equiv M^q \cdot M^{q\dagger}$ rather than the previously assumed
Hermitian $M^q$. The only assumption employed here is that the real part and
imaginary part of $\bf M^2$ can be, respectively, diagonalized by a common $\bf
U^q$ matrix. Such an assumption leads to a $\bf M^2$ pattern which depends on
only five parameters and can be diagonalized analytically by a $\bf U^q$ matrix
which depends on only two of the parameters. Two of the derived mass
eigenvalues are predicted degenerate if one of the parameters $\bf C ~(C')$ in
up- (down-) quark sector is zero. As the $\bf U^q$ patterns are obtained,
thirty-six $V_{CKM}$ candidates are yielded and only eight of them, classified
into two groups, fit empirical data within the order of $O(\lambda)$. One of
the groups is further excluded in a numerical test, and the surviving group
predicts that the degenerate pair in a quark type are the lightest and the
heaviest generations rather than the lighter two generations assumed in
previous researches. However, there is still one unsatisfactory prediction in
this research, a quadruple equality in which four CKM elements of very
different values are predicted to be equal. It indicates the $\bf M^2$ pattern
studied here is still oversimplified by that employed assumption and the
ultimate solution can only be obtained by diagonalizing the unsimplified $\bf
M^2$ matrix containing nine parameters directly. The $V_{CKM}$ presented here
is already very close to such an ultimate CPV solution.
