#include <bits/stdc++.h>
#define N 100011
#define pii pair<int,int>
#define s1 first
#define s2 second
using namespace std;
int t,n,m;vector<int> G[N],nG[N];
int deg[N],fa[N],siz[N];bool vis[N];
int get(int a){return fa[a]==a?a:fa[a]=get(fa[a]);}
void merge(int a,int b)
{
	a=get(a);b=get(b);
	if(a==b)return;
	fa[b]=a;siz[a]+=siz[b];
}
vector<pii> vv;
vector<int> ans[N];
int main()
{
	scanf("%d",&t);while(t--)
	{
		scanf("%d%d",&n,&m);
		for(int i=1;i<=n;++i)G[i].clear(),nG[i].clear(),deg[i]=0;
		for(int i=1;i<=m;++i)
		{
			int u,v;scanf("%d%d",&u,&v);
			G[u].push_back(v);G[v].push_back(u);
			++deg[u];++deg[v];
		}
		for(int i=1;i<=n;++i)
		{
			fa[i]=i;vis[i]=0;siz[i]=1;
		}
		vv.clear();
		for(int i=1;i<=n;++i)vv.push_back({deg[i],i});
		sort(vv.begin(),vv.end());
		// printf("vv:");for(pii x:vv)printf("{%d,%d} ",x.s1,x.s2);putchar(10);
		for(int i=1;i<=n;++i)
		{
			for(int j:G[i])if(deg[i]>deg[j]||deg[i]==deg[j]&&i>j)nG[i].push_back(j);
		}
		for(int i=1;i<=n;++i)ans[i].clear();
		bool ok=1;
		for(int i=0;i<vv.size();++i)
		{
			int u=vv[i].s2;
			for(int v:nG[u])if(!vis[get(v)])ans[u].push_back(v),vis[get(v)]=1;
			int sz=0;
			for(int v:nG[u])if(vis[get(v)])sz+=siz[get(v)],vis[get(v)]=0;
			if(sz!=nG[u].size())
			{
				ok=0;break;
			}
			for(int v:ans[u])merge(u,v);
		}
		if(!ok)
		{
			printf("No\n");
		}
		else
		{
			printf("Yes\n");
			for(int i=0;i<vv.size();++i)
			{
				int u=vv[i].s2;
				printf("%d %d ",u,(int)ans[u].size());
				for(int v:ans[u])printf("%d ",v);putchar(10);
			}
		}
	}
}