为什么18行的else会报错

package flow;

import java.util.Scanner;

public class ScoreAssess {

 public static void main(String[] args) { 
      
   System.out.println("请输入成绩");
   Scanner sc=new Scanner(System.in);
   int score = sc.nextInt();
   if(score>=90)
    System.out.println("优");
   else if(score>=80)
    System.out.println("良");
   else if(score>=60);
       System.out.println("中");
   else
    System.out.println("不及格");