it looks like this now :
@if (IsSectionDefined("left"))
{
@RenderSection("left")
}
else
{
@Html.Widget("left_side_column_before")
<div class="clear">
</div>
@Html.Action("CategoryNavigation", "Catalog", new { currentCategoryId = currentCategoryId, currentProductId = currentProductId })
<div class="clear">
</div>
@Html.Action("ManufacturerNavigation", "Catalog", new { currentManufacturerId = currentManufacturerId })
<div class="clear">
</div>
@Html.Action("NewsletterBox", "Newsletter")
<div class="clear">
</div>
@Html.Widget("left_side_column_after")
}