8. (10 points) Place seven consecutive natural numbers at the intersection points $A, B, C, D, E, F, G$ of five circles, such that the sum of the numbers on each circle is equal. If all the numbers filled in are greater than 0 and no more than 10, then the number filled at point $G$ is.
6
【Analysis】First, analyze the relationships between these numbers, equal quantities, and quantities with multiple relationships, and enumerate attempts.
【Solution】Solution: According to the problem, we have:
$$
\begin{array}{l}
A+B=A+C+D=B+E+F=C+F+G=D+E+G . \\
C+D=B, E+F=A . \\
C+F+G+D+E+G=A+B+A+B
\end{array}
$$
$2 G=A+B$. (The sum is even)
The letter $G$ is estimated to be among the middle numbers $5,6,7$. The letter $A$ cannot be 1,2. The letter $B$ is relatively large.
Trying $A=3, B=9, G=6 . E+F=3, C+D=9$. The sum of equal numbers is 12. Therefore, $F=1 . C=5 . E$ $=2, D=4$. The conditions are satisfied.

The answer is: 6