//teja349
#include <bits/stdc++.h>
#include <vector>
#include <set>
#include <map>
#include <string>
#include <cstdio>
#include <cstdlib>
#include <climits>
#include <utility>
#include <algorithm>
#include <cmath>
#include <queue>
#include <stack>
#include <iomanip> 
//setbase - cout << setbase (16); cout << 100 << endl; Prints 64
//setfill -   cout << setfill ('x') << setw (5); cout << 77 << endl; prints xxx77
//setprecision - cout << setprecision (14) << f << endl; Prints x.xxxx
//cout.precision(x)  cout<<fixed<<val;  // prints x digits after decimal in val

using namespace std;
#define f(i,a,b) for(i=a;i<b;i++)
#define rep(i,n) f(i,0,n)
#define fd(i,a,b) for(i=a;i>=b;i--)
#define pb push_back
#define mp make_pair
#define vi vector< int >
#define vl vector< ll >
#define ss second
#define ff first
#define ll long long
#define pii pair< int,int >
#define pll pair< ll,ll >
#define sz(a) a.size()
#define inf (1000*1000*1000+5)
#define all(a) a.begin(),a.end()
#define tri pair<int,pii>
#define vii vector<pii>
#define vll vector<pll>
#define viii vector<tri>
#define mod (1000*1000*1000+7)
#define pqueue priority_queue< int >
#define pdqueue priority_queue< int,vi ,greater< int > >
#define flush fflush(stdout) 
#define primeDEN 727999983
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

string s[1234];
int visit[1234][1234];
int check(int a,int b){
	int i,j;
	rep(i,2){
		rep(j,2){
			if(s[i+a][j+b]=='#'){
				return 0;
			}
		}
	}
	rep(i,2){
		rep(j,2){
			visit[i+a][j+b]=1;
		}
	}
	return 0;

}
int main(){
    std::ios::sync_with_stdio(false); cin.tie(NULL);
    int t;
    cin>>t;
    while(t--){
    	int n,m;
    	cin>>n>>m;
    	int i,j;
    	rep(i,n){
    		cin>>s[i];
    		rep(j,m){
    			visit[i][j]=0;
    		}
    	}
    	rep(i,n-1){
    		rep(j,m-1){
    			check(i,j);
    		}
    	}
    	int flag=0;
    	rep(i,n){
    		rep(j,m){
    			if(s[i][j]=='.' && visit[i][j]==0){
    				flag=1;
    			}
    		}
    	}
    	if(flag==0){
    		cout<<"YES"<<endl;
    	}
    	else{
    		cout<<"NO"<<endl;
    	}
    }
    return 0;   
}