53515
As described above , any completely regular space is regular , and any T space that is not Hausdorff ( and hence not preregular ) cannot be regular .
 T, Hausdorff
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 T, Hausdorff