#include<iostream>
#define ll long long
using namespace std;
const ll mod=1000000007;
ll t,N,s[1000010],inv[1000010],ans,n,m;
int main(){
	cin>>t;
	s[1]=s[0]=inv[1]=inv[0]=1;
	for(ll i=2;i<=1000000;i++){
		s[i]=s[i-1]*i%mod;
		inv[i]=(mod-mod/i)*inv[mod%i]%mod;
		//cout<<inv[i]<<endl;
	}
	for(ll i=1;i<=1000000;i++)inv[i]=inv[i-1]*inv[i]%mod;
	for(ll i=0;i<t;i++){
		cin>>n>>m; 
		ans=s[n+m-2]*inv[n-1]%mod*inv[m-1]%mod*(n*m-1)%mod;
		cout<<ans<<endl;
	}
	 
	return 0;
}