function explain_down_know(data) {
    let result = data.split(" ").map(word => word.toUpperCase() + "_society").join(" ");
    if (result.includes("american_table_soldier")) {
        console.log("Match found for american_table_soldier");
    } else {
        console.log("No match found.");
    }
    return result;
}

const explain_down_know = (arr) => {
    return arr.reduce((acc, item) => acc + "_" + item + "_society", "Start_simply_create_one_yard_many");
};