#include<bits/stdc++.h>

using namespace std;

#define irep(i,l,r) for(ll i = l; i <= r; ++ i)
typedef long long ll;
#define IOS ios::sync_with_stdio(false),cin.tie(0);

const int N = 200000 + 7;

void solve(){
	int n, m;
	cin >> n >> m;
	vector<vector<int>>g(n);
	vector<int>deg(n);
	set<array<int, 2>>st;
	irep(i, 0, m - 1){
		int x, y;
		cin >> x >> y;
		-- x, -- y;
		g[x].push_back(y);
		g[y].push_back(x);
		deg[x] ++, deg[y] ++;
	}

	irep(x, 0, n - 1){
		st.insert({deg[x], (int)x});
	}

	vector<int>q;
	while(st.size()){
		auto [DD, idx] = *st.rbegin();
		deg[idx] = -1;
		st.erase(*st.rbegin());
		q.push_back(idx);
		for(int y : g[idx]){
			st.extract({deg[y], y});
			deg[y] --;
			if(deg[y] >= 0)st.insert({deg[y], y});
		}
	}
	reverse(q.begin(), q.end());
	vector<vector<int>>ans(n);
	vector<int>fa(n), sz(n), getp(n);
	irep(i, 0, n - 1){
		fa[i] = i, sz[i] = 1;
//        cerr << q[i] + 1 << ' ';
	}
	function<int(int)>find = [&](int x){
		if(fa[x] == x)return fa[x];
		fa[x] = find(fa[x]);
		return fa[x];
	};
	auto merge = [&](int x, int y){
		x = find(x), y = find(y);
		if(sz[x] > sz[y])swap(x, y);
		sz[y] += sz[x];
		fa[x] = y;
	};
	irep(i, 0, n - 1){
		getp[q[i]] = i;
	}
	irep(i, 0, n - 1){
//        cerr << endl << i << endl;
		int x = q[i];
		map<int, int>ff;
		for(int y : g[x]){
			if(getp[y] > getp[x])continue;
			ff[find(y)] ++;
            if(ff[find(y)] == 1)
    			ans[i].push_back(y);
		}
		for(int y : ans[i]){
			if(sz[find(y)] != ff[find(y)]){
				cout << "No\n";
				return;
			}
        }
        for(int y : ans[i]){
            merge(x, y);
        }
	}
	cout << "Yes\n";
//    return;
	irep(i, 0, n - 1){
		cout << q[i] + 1 << ' ' << ans[i].size();
		for(int pp : ans[i])cout << ' ' << pp + 1;
		cout << '\n';
	}
}

int main(){
	IOS
	int T;
	cin >> T;
	while(T --){
		solve();
	}
}