#include <iostream>
#include <vector>


void ProcessOneTest(size_t number_of_test) {
        size_t rows, colums, escape;
        std::cin >> rows >> colums >> escape;
        if (escape == rows*colums - 1) {
            std::cout << "Case #" << number_of_test << ": "<< "IMPOSSIBLE\n";
            return;
        }
        if (colums == 1) {
            std::cout << "Case #" << number_of_test << ": "<< "POSSIBLE\n";
            for (size_t index = 0; index < rows - escape; ++index) {
                if (index != rows - escape - 1) {
                    std::cout << "S\n";
                } else {
                    std::cout << "N\n";
                }
            }
            for (size_t index = rows - escape; index < rows; ++index) {
                std::cout << "S\n";
            }
            return;
        }
        std::vector<std::vector<char>> doors(rows, std::vector<char>(colums, ' '));
        size_t id = 0;
        do {
            if (escape < colums) {
                break;
            }
            escape -= colums;
            for (size_t index = 0; index < colums; ++index) {
                doors[id][index] = 'E';
            }
            ++id;
        } while (true);
        if (escape != 0) {
            if (escape != colums - 1) {
                for (size_t index = 0; index < colums - escape; ++index) {
                    if (index != colums - escape - 1) {
                        doors[id][index] = 'E';
                    } else {
                        doors[id][index] = 'W';
                    }
                }
                for (size_t index = colums - escape; index < colums; ++index) {
                    doors[id][index] = 'E';
                }
                ++id;
            } else {
                for (size_t index = 1; index < colums; ++index) {
                    doors[id][index] = 'E';
                }
                doors[id][0] = 'S';
                ++id;
                doors[id][0] = 'N';
                for (size_t index = 1; index < colums; ++index) {
                    if (index != colums - 1) {
                        doors[id][index] = 'E';
                    } else {
                        doors[id][index] = 'W';
                    }
                }
                ++id;
            }
        }
        while (id != rows) {
            for (size_t index = 0; index < colums; ++index) {
                if (index != colums - 1) {
                    doors[id][index] = 'E';
                } else {
                    doors[id][index] = 'W';
                }
            }
            ++id;
        }
        std::cout << "Case #" << number_of_test << ": POSSIBLE\n";
        for (size_t index_first = 0; index_first < rows; ++index_first) {
            for (size_t index_second = 0; index_second < colums; ++index_second) {
                std::cout << doors[index_first][index_second];
            }
            std::cout << '\n';
        }
}

int main() {
    std::ios_base::sync_with_stdio(false);
    std::cin.tie(nullptr);
    size_t t;
    std::cin >> t;
    for (size_t number_of_test = 1; number_of_test <= t; ++number_of_test) {
        ProcessOneTest(number_of_test);
    }
    return 0;
}