diff --git a/【实践课外】0.熟悉编程环境/7-1 重要的话说三遍.c b/【实践课外】0.熟悉编程环境/7-1 重要的话说三遍.c
new file mode 100644
index 0000000..18a40cb
--- /dev/null
+++ b/【实践课外】0.熟悉编程环境/7-1 重要的话说三遍.c	
@@ -0,0 +1,9 @@
+#include <stdio.h>
+
+int main() {
+    printf("I'm gonna WIN!\n");
+    printf("I'm gonna WIN!\n");
+    printf("I'm gonna WIN!\n");
+
+    return 0;
+}
diff --git a/【实践课外】0.熟悉编程环境/7-2 计算平均分.c b/【实践课外】0.熟悉编程环境/7-2 计算平均分.c
new file mode 100644
index 0000000..2bc4111
--- /dev/null
+++ b/【实践课外】0.熟悉编程环境/7-2 计算平均分.c	
@@ -0,0 +1,12 @@
+#include <stdio.h>
+
+int main() {
+    int math = 87;
+    int eng = 72;
+    int comp = 93;
+    int average = (math + eng + comp) / 3;
+
+    printf("math = %d, eng = %d, comp = %d, average = %d\n", math, eng, comp, average);
+
+    return 0;
+}
diff --git a/【实践课外】0.熟悉编程环境/7-3 计算长方形的周长和面积.c b/【实践课外】0.熟悉编程环境/7-3 计算长方形的周长和面积.c
new file mode 100644
index 0000000..86ca86e
--- /dev/null
+++ b/【实践课外】0.熟悉编程环境/7-3 计算长方形的周长和面积.c	
@@ -0,0 +1,12 @@
+#include <stdio.h>
+
+int main() {
+    int a, b;
+
+    scanf("%d %d", &a, &b);
+
+    printf("C = %d\n", (a + b) * 2);
+    printf("S = %d\n", a * b);
+
+    return 0;
+}
diff --git a/【实践课外】0.熟悉编程环境/7-4 简单最值.c b/【实践课外】0.熟悉编程环境/7-4 简单最值.c
new file mode 100644
index 0000000..10adadb
--- /dev/null
+++ b/【实践课外】0.熟悉编程环境/7-4 简单最值.c	
@@ -0,0 +1,21 @@
+#include <stdio.h>
+
+int max(int a, int b, int c) {
+    if (a > b && a > c) {
+        return a;
+    } else if (b > a && b > c) {
+        return b;
+    } else {  // c > a && c > b
+        return c;
+    }
+}
+
+int main() {
+    int a, b, c;
+
+    scanf("%d%d%d", &a, &b, &c);
+
+    printf("%d\n", max(a, b, c));
+
+    return 0;
+}