public function behaviors()
{
    return [
        // ...
        'translatable' => [
            'class' => TranslatableBehavior::className(),
            // 'translationRelationName' => 'translations',
            // 'translationLanguageAttrName' => 'language',
            // 'attributeNamePattern' => '%name% [%language%]',
            'translationAttributeList' => [
                'title',
                'description',
            ],
        ],
    ];
}

// product is an active record model with translatable behavior
$product = new Product();

// sets translation for default application language
$product->title = 'PhpStrom 2018.1';
$product->description = 'Лицензия PhpStrom IDE версия 2018.1';

// gets translation for English language
$translation = $product->getTranslation('en');
$translation->title = 'PhpStrom 2018.1';
$translation->description = 'License of the PhpStrom IDE version 2018.1';

// sets description for French language
$product->translateTo('fr')->description = 'La licence de PhpStorm IDE la version 2018.1';

$product->insert();

$product = Product::find()
    ->where(['id' => 1])
    ->with('translations')
    ->one()
;

// gets translation for English language
$product->translateTo('en')->description; // License of the PhpStrom IDE version 2018.1
// gets translation for French language
$product->translateTo('fr')->description; // La licence de PhpStorm IDE la version 2018.1

// check whether Ukrainian translation not exists
if (!$product->hasTranslation('uk')) {
    $product->translateTo('uk')->description = 'Ліцензія PhpStrom IDE версія 2018.1';
}

// update Enlish translation
$product->translateTo('en')->title = 'PhpStorm IDE';

$product->update();