import java.io.*;
import java.util.*;
public class C{
    // static PrintWriter out=new PrintWriter(System.out);
    static BufferedWriter out=new BufferedWriter(new OutputStreamWriter(System.out));
    static FastReader in=new FastReader();
    static int MAX=(int)1e6+10;
    public static void main(String[] args) throws IOException{
        int T;
        T=in.nextInt();
//      T=1;
        for(int t=1; t<=T; ++t) solve(t);
        out.flush();
        out.close();
    }
    static void decByOne(TreeMap<Integer, Integer> freq, int key){
        freq.put(key, freq.get(key)-1);
        if(freq.get(key)==0) freq.remove(key);
    }
    static void incByOne(TreeMap<Integer, Integer> freq, int key){
        freq.put(key, freq.getOrDefault(key, 0)+1);
    }
    static boolean possible(TreeMap<Integer, Integer> freq, int sum, boolean printSol) throws IOException {
        if(freq.size()==0) return true;
        int last=freq.lastKey();
        decByOne(freq, last);
        int required=sum-last;
        boolean isPossible;
        if(!freq.containsKey(required)){
            isPossible=false;
        }
        else{
            decByOne(freq, required);
            if(printSol) out.write(last+" "+required+"\n");
            isPossible=possible(freq, last, printSol);
            incByOne(freq, required);
        }
        incByOne(freq, last);
        return isPossible;
    }
    static void solve(int testCase) throws IOException{
        // out.print("Case #"+testCase+": ");
        TreeMap<Integer, Integer> freq=new TreeMap<>();
        int n=in.nextInt();
        int[] arr=new int[2*n];
        for(int i=0; i<2*n; ++i){
            arr[i]=in.nextInt();
            freq.put(arr[i], freq.getOrDefault(arr[i], 0)+1);
        }
        Utility.fastSort(arr);
        int last=arr[2*n-1];
        // Utility.debug(last);
        decByOne(freq, last);
        for(int j=2*n-2; j>=0; --j){
            int ele=arr[j];
            decByOne(freq, ele);
            int sum=last+ele;
            // Utility.debug("Sum is", sum);
            // out.println(freq.toString());
            if(possible(freq, last, false)){
                out.write("YES\n");
                out.write(sum+"\n");
                out.write(last+" "+ele+"\n");
                possible(freq, last, true);
                return;
            } else{
                incByOne(freq, ele);
            }
        }
        out.write("NO\n");

    }
    static class Utility{
        static final String sep="#".repeat(10);
        static int gcd(int a, int b){
            if(b==0) return a;
            return gcd(b, a%b);
        }
        static long gcd(long a, long b){
            if(b==0) return a;
            return gcd(b, a%b);
        }
        static void fastSort(int[] arr){
            ArrayList<Integer> a=new ArrayList<>();
            for(int x: arr) a.add(x);
            Collections.sort(a);
            for(int i=0; i<a.size(); ++i) arr[i]=a.get(i);
        }
        static void fastSort(long[] arr){
            ArrayList<Long> a=new ArrayList<>();
            for(long x: arr) a.add(x);
            Collections.sort(a);
            for(int i=0; i<a.size(); ++i) arr[i]=a.get(i);
        }
        // static void debug(int[] arr){
        //     out.println(sep);
        //     out.println("[DEBUG] " + Arrays.toString(arr));
        //     out.println(sep);
        // }
        // static void debug(long[] arr){
        //     out.println(sep);
        //     out.println("[DEBUG] " + Arrays.toString(arr));
        //     out.println(sep);
        // }
        // static void debug(Object... args){
        //     out.println(sep); out.print("[DEBUG] ");
        //     for(Object o: args) out.print(o + " ");
        //     out.println(); out.println(sep);
        // }
    }
    static class FastReader{
        BufferedReader br;
        StringTokenizer st;
        public FastReader(){
            br=new BufferedReader(new InputStreamReader(System.in));
        }
        String next(){
            while(st==null||!st.hasMoreElements()){
                try{
                    st=new StringTokenizer(br.readLine());
                }catch(IOException e){
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }
        int nextInt(){
            return Integer.parseInt(next());
        }
        long nextLong(){
            return Long.parseLong(next());
        }
        double nextDouble(){
            return Double.parseDouble(next());
        }
        String nextLine(){
            String str="";
            try{
                str=br.readLine();
            }catch(IOException e){
                e.printStackTrace();
            }
            return str;
        }
    }
}