diff --git a/stage04-composite-types/03-maps/main.go b/stage04-composite-types/03-maps/main.go
index 9641c14..64b6196 100644
--- a/stage04-composite-types/03-maps/main.go
+++ b/stage04-composite-types/03-maps/main.go
@@ -7,13 +7,13 @@ func exercise1() map[string]int {
 
 	// 创建一个map，键为string类型，值为int类型
 	// 添加"张三": 90, "李四": 85, "王五": 95
-	scores := ____
+	scores := make(map[string]int)
 
-	scores["张三"] = ____
-	scores["李四"] = ____
-	scores["王五"] = ____
+	scores["张三"] = 90
+	scores["李四"] = 85
+	scores["王五"] = 95
 
-	return ____
+	return scores
 }
 
 func exercise2() string {
@@ -25,7 +25,7 @@ func exercise2() string {
 		"李四": 85,
 	}
 
-	score, exists := ____
+	score, exists := scores["李四"]
 
 	if exists {
 		fmt.Printf("李四的分数是: %d\n", score)
@@ -45,13 +45,13 @@ func exercise3() int {
 		"赵六": 88,
 	}
 
-	sum := ____
+	sum := 0
 
-	for ____, score := range ____ {
-		sum += ____
+	for _, score := range scores {
+		sum += score
 	}
 
-	return ____
+	return sum
 }
 
 func exercise4() map[string]int {
@@ -64,9 +64,9 @@ func exercise4() map[string]int {
 		"王五": 95,
 	}
 
-	____(scores, "李四")
+	delete(scores, "李四")
 
-	return ____
+	return scores
 }
 
 func exercise5() []string {
@@ -81,19 +81,19 @@ func exercise5() []string {
 		"钱七": 92,
 	}
 
-	var topStudents ____
+	var topStudents []string
 
-	for name, score := range ____ {
-		if score >= ____ {
-			topStudents = append(____, ____)
+	for name, score := range scores {
+		if score >= 90 {
+			topStudents = append(topStudents, name)
 		}
 	}
 
-	return ____
+	return topStudents
 }
 
 func main() {
-	fmt.Println("=== map 练习 ===\n")
+	fmt.Println("=== map 练习 ===")
 
 	result1 := exercise1()
 	fmt.Printf("练习1结果: %v\n", result1)