#include <bits/stdc++.h>
using namespace std;
const int INF = 0x3f3f3f3f;
int main() {
  ios::sync_with_stdio(false);
  int t;
  cin >> t;
  while (t--) {
    string s, t;
    cin >> s >> t;
    vector<int> each[26];
    int n, m;
    n = s.length();
    m = t.length();
    for (int i = 0; i < n; ++i) {
      each[s[i] - 'a'].push_back(i);
    }
    int las = INF, res = 0;
    for (int i = 0; i < m; ++i) {
      if (upper_bound(each[t[i] - 'a'].begin(), each[t[i] - 'a'].end(), las) !=
          each[t[i] - 'a'].end()) {
        las =
            *upper_bound(each[t[i] - 'a'].begin(), each[t[i] - 'a'].end(), las);
      } else {
        if (each[t[i] - 'a'].empty()) {
          res = -1;
          break;
        } else {
          res++;
          las = each[t[i] - 'a'][0];
        }
      }
    }
    cout << res << endl;
  }
  return 0;
}
