fix text

Author: diberry

articles/cognitive-services/LUIS/luis-reference-regions.md

@@ -23,9 +23,9 @@ There are three LUIS authoring portals, based on region. You must author and pub
 
 |LUIS|Authoring region|Azure region name|
 |--|--|--|
-|[www.luis.ai][www.luis.ai] <br>[preview](https://preview.luis.ai)|U.S.<br>not Europe<br>not Australia| `westus`|
-|[au.luis.ai][au.luis.ai] <br>[preview](https://preview.au.luis.ai/)|Australia| `australiaeast`|
-|[eu.luis.ai][eu.luis.ai] <br>[preview](https://preview.eu.luis.ai/)|Europe|`westeurope`|
+|[www.luis.ai][www.luis.ai] <br>[preview.luis.ai](https://preview.luis.ai)|U.S.<br>not Europe<br>not Australia| `westus`|
+|[au.luis.ai][au.luis.ai] <br>[preview.au.luis.ai](https://preview.au.luis.ai)|Australia| `australiaeast`|
+|[eu.luis.ai][eu.luis.ai] <br>[preview.eu.luis.ai](https://preview.eu.luis.ai)|Europe|`westeurope`|
 
 Authoring regions have [paired fail-over regions](https://docs.microsoft.com/azure/best-practices-availability-paired-regions).