#include<iostream>
#include<algorithm>
#include<string>
#include<stack>
#include<cstdio>
#include<map>
#include<functional>

using namespace std;

#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<string>
#include<cstring>

using namespace std;

int main(){
	string s;
	int n;
	char mozi[10][10] = {"abcde","fghij","klmno","pqrst","uvwxy","z.?! "};
    bool flag=true;
    
    cin>>n;
	for(int i=0; i<n; i++)
	{
		cin>>s;
		if(s.size()%2==1)
		{
			puts("NA");
			continue;
		}
		else
		{
			char str[201],kari[200];
			long int length = s.length();
			s.copy(str,length,0);
			for(int i=0; i<s.size(); i+=2)
			{
                if(0 <= (int)str[i]-49 <= 5 && 0 <= (int)str[i+1]-49 <= 4)
                    kari[i]=mozi[ (int)str[i]-49 ][ (int)str[i+1]-49 ];
                else
                    flag=false;
			}
            if(flag==true)
            {
                for(int i=0; i<s.size(); i+=2)
                {
                    cout<<kari[i];
                }
            }
            else
            {
                cout<<"NA";
            }
            puts("");
		}
    }
	return 0;
}