#include <bits/stdc++.h>
using namespace std;
void solve()
{
    int n,m;cin>>n>>m;
    vector<vector<pair<int,int>>> ve(n+1);
    for(int i=1;i<=m;i++){
        int x,y;cin>>x>>y;
        ve[x].emplace_back(y,i);
        ve[y].emplace_back(x,i);
    }
    vector<int> siz(n+1,1);
    vector<int> f(n+1);iota(f.begin(),f.end(),0);
    function<int(int)> getf = [&](int x){
        if(x==f[x])return x;
        else return f[x]=getf(f[x]);
    };
    auto merge= [ &](int x,int y){
        x=getf(x),y=getf(y);
        if(x==y)return;
        f[x]=y;
        siz[y]+=siz[x];
    };
    vector<int>ok(m+1,1);
    vector<int>id(n);iota(id.begin(),id.end(),1);
    sort(id.begin(),id.end(),[&](int x,int y){
        return ve[x].size()>ve[y].size();
    }) ;
    vector<vector<int>>ve2(n+1);
    for(auto x:id){
        for(auto [to,id]:ve[x])if(ok[id]){
            ve2[x].push_back(to);
            ok[id]=0;
        }
    }
    vector<pair<int,vector<int>>> ans;
    for(int i=n-1;i>=0;i--){
        int x=id[i];
        vector<int> v;
        for(auto it:ve2[x])v.emplace_back(getf(it));
        sort(v.begin(),v.end());v.resize(unique(v.begin(),v.end())-v.begin());
        int sum=0;
        for(auto it:v)sum+=siz[it];
        // cout<<"x="<<x<<" sum="<<sum<<endl;
        if(sum!=ve2[x].size()){
            cout<<"No\n";return;
        }
        ans.emplace_back(x,v);
        for(auto it:v)merge(it,x);
    }
    cout<<"Yes\n";
    for(auto [x,v]:ans){
        cout<<x<<" ";
        cout<<v.size();
        for(auto it:v)cout<<" "<<it;;cout<<"\n";
    }
}
signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    int T;cin>>T;while(T--){
        solve();
    }
}
/*
3
3 0

4 4
1 2
2 3
3 4
2 4

5 5
1 2
2 3
3 4
4 5
2 4
*/