en месяцы склонения

function en(mounth) {
    if(mounth == '1'){
        return 'January'
    }
    if(mounth == '2'){
        return 'February'
    }
    if(mounth == '3'){
        return 'March'
    }
    if(mounth == '4'){
        return 'April'
    }
    if(mounth == '5'){
        return 'May'
    }
    if(mounth == '6'){
        return 'June'
    }
    if(mounth == '7'){
        return 'July'
    }
    if(mounth == '8'){
        return 'August'
    }
    if(mounth == '9'){
        return 'September'
    }
    if(mounth == '10'){
        return 'October'
    }
    if(mounth == '11'){
        return 'November'
    }
    if(mounth == '