Sentence:  La^utner , for his part , `` belonged to the present-day race of small artists , who do not demand the utmost of themselves '' , and the bitter description of the type includes such epithets as `` wretched little poseurs '' , the devastating indictment `` they do not <WSD>know</WSD> how to be wretched decently and in order '' , and the somewhat extreme prophecy , so far not fulfilled : `` They will be destroyed '' . 
Meaning of the word marked with <WSD> tags:  know how to do or perform something