您可以将特色图像（或特色缩略图）用于此类型的功能。您可以控制使用的图像大小。。。它不必是“缩略图”大小。从codex:

get_the_post_thumbnail(get_the_ID(), \'thumbnail\');     // Thumbnail
get_the_post_thumbnail(get_the_ID(), \'medium\');        // Medium resolution
get_the_post_thumbnail(get_the_ID(), \'large\');         // Large resolution
get_the_post_thumbnail(get_the_ID(), \'full\');          // Original resolution

get_the_post_thumbnail(get_the_ID(), array(100,100) ); // Other resolutions

while have_posts(): the_post();
    ?>
    <h2><?php the_title() ?></h2>
    <? echo get_the_post_thumbnail(get_the_ID(), \'large\'); ?>
    <? the_excerpt();
endwhile;

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正如Andy在下面提到的，您还可以将自己的自定义尺寸添加到可能性列表中。在函数中添加几行代码。php文件：

function my_image_sizes()
{
    if ( function_exists( \'add_theme_support\' ) ) {
        add_theme_support( \'post-thumbnails\' );  
    }

    if ( function_exists( \'add_image_size\' ) ) { 
        //300 pixels wide (and unlimited height)
        add_image_size( \'category-thumb\', 300, 9999 ); 
        // Cropped to exactly 220px wide and 180 high
        add_image_size( \'homepage-thumb\', 220, 180, true ); 
    }
}
add_action(\'init\', \'my_image_sizes\');