In the process of Chinese language learning, some students may say 死着 after they learn 看着 which is as a matter of fact incorrect. To answer this question, the learners need to learn something about durative verbs and non-durable verbs. They are all verbs but the verbs like 看and坐can take the character 着while 死and结婚are not allowed to take 着after them. In order to make the question asked in the title clear, both kinds of verbs will be introduced in the following parts.

The so-called durative verbs are the words such as 看、坐、等、学习and听, which indicate the act will last for long and can be done repeatedly. On the contrary, the words like 死、结婚、离开、来、认识and出国are non-durable verbs because the acts they indicate will not last and disappear soon. The point that the foreign students who attend to school to study Mandarin need to know is that 着can be used after durative verbs like 看着书and坐着 while it is incorrect to say 死着and丢着.

In Chinese language, there are a number of durative verbs but limited non-durative verbs. Therefore, in the Chinese language teaching as a foreign language, when the teachers meet the non-durative verbs, they should tell the students that those verbs can be followed by 着. For example, the sentence 他正死着is incorrect.

In addition, we can say 看了两个小时书了but do not say 来了两个月中国了, which are also related to the durative verbs. The acts showed with the verbs of 看type are mostly durative. We can say both 他看了两个小时书了and她看书看了两个小时了but not 他看书两个小时了. On the contrary, when teachers teach Mandarin language, they need to tell the students that the actions produced by the verbs of 离开classification such as 离开、来、去and回 are not durative. But it can appear only in the third sentence type like 哥哥离开北京半年了but not 哥哥离开半年北京了and哥哥离开北京离开半年了.