#include <iostream>
#include <vector>

int main() {
    int t;
    std::cin >> t;

    while (t--) {
        int n;
        std::cin >> n;

        std::string s;
        std::cin >> s;

        auto ws = std::vector<int>{};
        for (int i = 0; i < 2*n; i++) {
            if (s[i] == 'W')
                ws.push_back(i);
        }

        int idx = 0;

        for (int i = 0; i < n; i++) {
            // we want to pair with next white
            if (s[i] == 'W') {
                if (ws[idx] == i) {
                    idx += 1;
                } else {
                    continue;
                }
            }

            if (idx >= n) {
                std::cout << "NO\n";
                goto next;
            }
            // std::cout << "pairing " << i << " with " << ws[idx] << '\n';
            idx += 1;
        }

        std::cout << "YES\n";
        next:;
    }
}