如何在laravel中添加具有外键值的表引用另一个表？

Model 1:

型号1：

namespace App;
use Illuminate\Database\Eloquent\Model;

class productDescription extends Model
{
    protected $table="ProductDescription";
    protected $connection="mysql";

    public function productPricing()
    {
        return $this->belongsTo(priceInfo::class);
    }
    public function salesPackage()
    {
        return $this->hasMany(packageModel::class);
    }
}
namespace App;
use Illuminate