#include <bits/stdc++.h>
using namespace std;
int n, m, k, s, nodes;
vector<vector<int>> adj;
vector<int> namelen;
vector<int> preflen;
vector<int> par;
vector<int> tin, tout;
int timer = 0;
void dfs(int u, int len, int p = -1) {
len += namelen[u];
if (u <= n)
len++;
preflen[u] = len;
tin[u] = timer++;
for (int v : adj[u])
if (v != p)
dfs(v, len, u);
tout[u] = timer++;
}
bool anc(int u, int anc) { return tin[anc] < tin[u] && tout[u] < tout[anc]; }
int main() {
cin >> n >> m >> k >> s;
nodes = n + 1 + m;
adj.resize(nodes);
namelen.resize(nodes);
par.resize(nodes);
namelen[0] = 0;
par[0] = -1;
for (int i = 1; i <= n; i++) {
int p, l;
cin >> p >> l;
adj[i].push_back(p);
adj[p].push_back(i);
par[i] = p;
namelen[i] = l;
}
for (int i = 0; i < m; i++) {
int p, l;
cin >> p >> l;
adj[i + n + 1].push_back(p);
adj[p].push_back(i + n + 1);
namelen[i + n + 1] = l;
par[i + n + 1] = p;
}
tin.resize(nodes);
tout.resize(nodes);
preflen.resize(nodes);
dfs(0, 0);
vector<bool> ans(m);
for (int i = 0; i < m; i++) {
int file = i + n + 1;
if (preflen[file] == k)
ans[i] = 1;
else if (k < preflen[file])
ans[i] = 0;
else {
int symend = file;
bool is_possible = 0;
while (symend != -1) {
for (int symstart = 0; symstart <= n; symstart++) {
if (anc(symstart, symend)) {
is_possible |=
0 == (k - preflen[file]) %
(s + 1 + preflen[symstart] - preflen[symend]);
} else {
is_possible |= k == s + 1 + preflen[file] -
(symend == 0 ? 0 : preflen[par[symend]]) +
preflen[symstart];
}
}
symend = par[symend];
}
ans[i] = is_possible;
}
}
for (bool a : ans)
if (a)
cout << "YES\n";
else
cout << "NO\n";
cout << flush;
return 0;
}
