#include <bits/stdc++.h>
#define ll long long
#define pb push_back
#define ull unsigned long long
#define pi pair<int,int>
#define vi vector<ll>
#define sc second
#define ft first
#define PI 3.14159265
const ll N=2e5+10,MOD=998244353;
using namespace std;
ll n,t=1,m;
int main(){
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    cin >> t;
    while(t--){
        cin >> n; ll mx=0,ok=0; map<int,int>mp; vi a;
        for(int i=0;i<n*2;i++){
                cin >> m; a.pb(m);
                mp[a[i]]++;
        }
        sort(a.rbegin(),a.rend());
        mx=a[0];
        for(int j=1;j<n*2;j++){
                map<int,int> fre=mp;
                vector<pi> anss;
                anss.pb({mx,a[j]});
                fre[a[j]]--;
                fre[mx]--;
                ll mx2=mx;
            for(int i=1;i<n*2;i++){
                    if(i==j||fre[a[i]]<=0) continue;
                    if(anss.size()==n) break;
                    if(fre[a[i]] && fre[mx2-a[i]] && a[i]!=mx2-a[i]){
                        fre[mx2-a[i]]--;
                        anss.pb({a[i],mx2-a[i]});
                        mx2=a[i];
                    }
                    else if(a[i]==mx2-a[i] && fre[a[i]]>1){
                        fre[mx2-a[i]]--;
                        anss.pb({a[i],mx2-a[i]});
                        mx2=a[i];
                    }
                    else
                        break;
                    fre[a[i]]--;
            }
            if(anss.size()==n){
                    cout << "YES\n"<< anss[0].ft + anss[0].sc << '\n';
                    for(pi x:anss) cout << x.ft <<' ' << x.sc <<'\n';
                    ok++;
                    break;
            }
        }
        if(!ok)
            cout << "NO\n";
    }
    return 0;
}
