救命，老師快救我。阿阿阿阿阿阿阿阿阿阿

import java.io.*;
import java.util.*;
public class jva110
{
public static void main(String arg[])
{
//取得出題數量
int userItemCoount = arg.length / 2;
//是否為使用者出題(自由出題)
Boolean isUserItem = (userItemCoount > 0);
//宣告題目陣列
String itemQue[];
String itemAns[];
//判斷是否是自由出題
if(isUserItem)
{
//是自由出題
//建立陣列
itemQue = new String[userItemCoount];
itemAns = new String[userItemCoount];
//寫入題目
for(int i=0;i<arg.length;i+=2)
{
itemQue[i/2] = arg[i];
itemAns[i/2] = arg[i+1];
}
}else{
//是預設題目
itemQue = new String[]{"電腦","資料庫","語法","學校","假期"};
itemAns = new String[]{"computer","database","syntax","school","Vocation"};
}
//紀錄開始時間
long startTime = new Date().getTime();
//顯示資訊
System.out.println("請將題目的中文字彙翻譯成英文單字!");
System.out.println("輸入英文單字答案後請按Enter鍵:\n");
//輸入擷取物件
Scanner scanner =new Scanner(System.in);
//宣告答對題目數變數
int Right=0;
//開始出題
for(int i=0;i<itemQue.length;i++)
{
System.out.println("第" + (i+1) +"題__ " + itemQue[i]);
String useInput = scanner.next();
String ans = itemAns[i].toLowerCass();
useInput = useInput.toLowerCass();
if(useInput.equals(ans))
{
System.out.println("答對了！");
Right++;
}else{
System.out.println("答錯了！");
System.out.println("正確答案是" + itemAns[i]+"\n");
}
}
//結算時間
long endTime = new Date().getTime();
long useTime = (endTime-startTime)/1000;
System.out.println("你使用了" + useTime + "秒，在" + itemQue.length + "題中答對了" + Right + "題");
}
}

複製代碼

老師，為甚麼一直有兩個錯誤訊息

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錯誤訊息如下& z6 S1 J) {2 `$ {
jva110.java:54: error: cannot find symbol2 C  m6 \8 X; w2 V0 Z0 Y8 c* I
                     String ans = itemAns.toLowerCass();' a% n, j% Y. {  |  x
                                             ^; `+ `% ~. [& x4 y4 L. e1 K
  symbol: method toLowerCass(). p' k" a. [- I$ ~" P
  location: class String
4 h2 u) z4 E3 D: H" Tjva110.java:55: error: cannot find symbol
' ]4 _" p2 C3 W0 u, `- @2 B9 ^3 u: V5 ]                      useInput = useInput.toLowerCass();
% A' v. q7 a# p* l) U/ k  b                                        ^
$ X  @# X" r6 G& F% a& a4 d  symbol: method toLowerCass()
; u* W, ]4 }: I) X* m0 ~$ |. k4 u  location: variable useInput of type String7 P% n. N! W2 \
2 errors