#include <bits/stdc++.h>
using namespace std;
const int MAXN = 1000010;
const long long LINF = 1LL * 1000000000 * 1000000000 + 9;
const double PI = acos(-1.0);
const string S =
    "What are you doing at the end of the world? Are you busy? Will you save "
    "us?";
const string Q =
    "What are you doing while sending ? Are you busy? Will you send ?";
const string S1 = "What are you doing while sending \"";
const string S2 = "\"? Are you busy? Will you send \"";
const string S3 = "\"?";
long long f[MAXN];
char cal(long long pos, int i) {
  if (i == 0) return S[pos];
  if (pos < S1.size()) return S1[pos];
  pos -= S1.size();
  if (pos < f[i - 1]) return cal(pos, i - 1);
  pos -= f[i - 1];
  if (pos < S2.size()) return S2[pos];
  pos -= S2.size();
  if (pos < f[i - 1]) return cal(pos, i - 1);
  pos -= f[i - 1];
  return S3[pos];
}
int main() {
  ios_base::sync_with_stdio(false);
  f[0] = S.size();
  for (int i = 1; i <= 100000; ++i) {
    f[i] = f[i - 1] * 2 + S1.size() + S2.size() + S3.size();
    if (f[i] > LINF) f[i] = LINF;
  }
  int N;
  cin >> N;
  for (int i = 0; i < N; ++i) {
    int a;
    long long b;
    cin >> a >> b;
    if (f[a] < b) {
      cout << ".";
      continue;
    }
    cout << cal(b - 1, a);
  }
  cout << endl;
  return 0;
}
