so that从句的判别

请分析下面两句子: When they heard that an elephant was passing by,they asked the driver to stop the beast so that they could have a"look". The doctor came in quietly so that he didn’t wake his patient. 以上两个复合句中都包括一个由so that引导的状语从句,但一是结果状语从句。两者堪称貌合而神离,有时光凭浅表颇难辨识。