#include <bits/stdc++.h>
using namespace std;
void solve(){
	int n,m;
	cin>>n>>m;
	vector<vector<int>> e(n+1),g(n+1);
	vector<int> d(n+1),b(n+1),fa(n+1),sz(n+1,1),id;
	for(int u,v;m--;) cin>>u>>v,e[u].push_back(v),e[v].push_back(u),d[u]++,d[v]++;
	set<array<int,2>> s;
	for(int i=1;i<=n;i++) s.insert({-d[i],i});
	while(s.size()){
		int x=(*begin(s))[1];
		s.erase(begin(s));
		b[x]=1;id.push_back(x);
		for(int y:e[x]) if(!b[y]){
			s.erase({-d[y],y});
			d[y]--;g[x].push_back(y);
			s.insert({-d[y],y});
		}
	}
	reverse(begin(id),end(id));
	iota(begin(fa),end(fa),0);
	auto getf=[&](int x){
		while(x!=fa[x]) x=fa[x]=fa[fa[x]];
		return x;
	};
	vector<set<int>> c(n+1);
	for(int x:id){
		for(int y:g[x]) c[x].insert(getf(y));
		for(int y:c[x]) fa[y]=x,sz[x]+=sz[y];
		if((int)g[x].size()!=sz[x]-1){
			cout<<"No\n";
			return;
		}
	}
	cout<<"Yes\n";
	for(int x:id){
		cout<<x<<" "<<c[x].size();
		for(int y:c[x]) cout<<" "<<y;
		cout<<"\n";
	}
}
int main(){
	cin.tie(0)->sync_with_stdio(0);
	int t;
	cin>>t;
	while(t--) solve();
	return 0;
}