Example: $3 A, B, C, D, E$ five people participate in an exam, with 7 questions, all of which are true or false questions. The scoring rule is: for each question, a correct answer earns 1 point, a wrong answer deducts 1 point, and no answer neither earns nor deducts points. Figure 1 records the answers of $A, B, C, D, E$ five people. It is known that $A, B, C, D$ each scored 2 points, how many points should $E$ get? What is the answer to each question?

保留源文本的换行和格式，直接输出翻译结果如下：

Example: $3 A, B, C, D, E$ five people participate in an exam, with 7 questions, all of which are true or false questions. The scoring rule is: for each question, a correct answer earns 1 point, a wrong answer deducts 1 point, and no answer neither earns nor deducts points. Figure 1 records the answers of $A, B, C, D, E$ five people. It is known that $A, B, C, D$ each scored 2 points, how many points should $E$ get? What is the answer to each question?
Let: Assign $k=1,2, \cdots, 7$. When the conclusion of the $k$-th question is correct, i.e., $x_{k}:=1$, if it is judged as correct (i.e., marked with the symbol “$\checkmark$”), then $x_{k}$ points are scored; if it is judged as incorrect (i.e., marked with the symbol “$X$”), then $-x_{k}$ points are scored. When the conclusion of the $k$-th question is incorrect, i.e., $x_{k}=-1$, if it is judged as correct, then $x_{k}$ points are scored; if it is judged as incorrect, then $-x_{k}$ points are scored. Since $A, B, C, D$ each scored 2 points, we can obtain the system of equations:
$$
\left\{\begin{array}{l}
x_{1}+0 \cdot x_{2}-x_{3}+x_{4}-x_{5}+x_{6}+x_{7}=2, \\
x_{1}-x_{2}+x_{3}+x_{4}-x_{5}-x_{6}+0 \cdot x_{7}=2, \\
0 \cdot x_{1}+x_{2}-x_{3}-x_{4}+x_{5}-x_{6}+x_{7}=2, \\
-x_{1}-x_{2}-x_{3}+x_{4}+x_{5}+0 \cdot x_{6}-x_{7}=2
\end{array}\right.
$$

Adding these four equations, we get
$$
x_{1}-x_{2}-2 x_{3}+2 x_{4}+0 \cdot x_{5}-x_{6}-x_{7}=8.
$$

Noting that $x_{i}= \pm 1(i=1,2, \cdots, 7)$, the left side of the above equation is $\leqslant 8$, and the right side is $=8$, hence $x_{1}=1, x_{2}=-1$, $x_{3}=-1, x_{4}=1, x_{6}=-1, x_{7}=1$. Substituting these results into the first equation of the system, we get $x_{5}=1$. Therefore, the 1st, 4th, 5th, and 7th questions are correct, and the 2nd, 3rd, and 6th questions are incorrect. Thus, according to the problem, $E$ scored 4 points.