There are some posts that have a photo that is 2x1, and others that have a photo of 1x2 (I mean those photos):

In addition, there are 3 columns. Bootstrap can do this easily:

<div class="row">
  <div class="col-md-4">
    <!-- conteudo -->
  </div>
  <div class="col-md-4">
    <!-- conteudo -->
  </div>
  <div class="col-md-4">
    <!-- conteudo -->
  </div>
</div>

Its logic, however, will have to analyze the image of each post inside the loop and verify:

Example

Note: This is not code that you can simply copy and paste into your application - it's just an attempt to show something appeared / p>

<?php 
 $colunas = 3;
 $coluna_corrente = 0;
 $duas_rows = false;
?>
<?php if ( have_posts() ) : ?>
 <?php while( have_posts() ) : the_post(); ?>
   <?php
    ++$coluna_corrente;
    if ( $coluna_corrente % $colunas == 0 ) {
      echo "<div class='row'>";
    }
    if ( tamanho_relativa_da_foto( $colunas, $post->foto ) < 2 ) { //esse função não existe
     echo '<div class="col-md-4">';
     the_title();
     //algo mais
     echo "</div>";
    } else if ( tamanho_relativa_da_foto( $colunas, $post->foto ) == 2 && !$duas_rows ) {
     echo '<div class="col-md-8">';
     //etc...
     echo '</div>';
    } else {
      $duas_rows = true;
      echo '<div class="col-md-4">';
      //...
      echo '</div>';
    }
    if ( $coluna_corrente == $colunas ) {
      echo "</div>";
    }
   ?>
 <?php endwhile; ?>
<?php endif; ?>

I suggest you use the bootstrap grid link to create the layouts. assembling the grids first and then implementing the loops. link

Well, I think it's something you have to use:

<div class="row">
  <div class="col-sm-6">  


    <?php if (have_posts()) : ?>
      <?php $number = 0 ?>
      <?php while (have_posts()) : the_post(); ?>
        <article id="post-<?php the_ID(); ?>" <?php post_class(); ?>>
         

            <h2><a href="<?php the_permalink(); ?>" title="<?php the_title(); ?>"><?php the_title(); ?></a></h2>
            <a href="<?php the_permalink(); ?>" title="<?php the_title(); ?>"><p><?php echo the_content(); ?></p></a>
          
 
        </article><!--col--> 
        <?php $number++; ?>      
      <?php endwhile; ?>
    <?php endif; ?>
  </div>  

</div>  

You define how the grid will be represented and then create the loop to bring wordpress information