diff --git a/lib/a.js b/lib/a.js
index eca3089..bccc719 100644
--- a/lib/a.js
+++ b/lib/a.js
@@ -1,12 +1,10 @@
 export const a = [
+  // Please sort these entries.
+
+  // Please *only* use casing if it adds something: `url` is fine, but it’s
+  // `a UN meeting` and `an un-united germany`.
   'U',
-  'UEFA',
-  'UK',
   'UN',
-  'UNHCR',
-  'URL',
-  'US',
-  'USB',
   'eucalypt*',
   'eucha*',
   'euchr*',
@@ -51,7 +49,9 @@ export const a = [
   'onewhere*',
   'oneyear',
   'ubiq*',
+  'uefa',
   'ugandan',
+  'uk',
   'ukase',
   'ukrain*',
   'ukulele',
@@ -60,6 +60,7 @@ export const a = [
   'unanim*',
   'unary',
   'unesco',
+  'unhcr',
   'uniam*',
   'uniart*',
   'uniat*',
@@ -78,12 +79,15 @@ export const a = [
   'uran*',
   'urate',
   'uri*',
+  'url',
   'urologist',
   'uruguay',
   'uruguayan',
   'uruguayans',
+  'us',
   'usab*',
   'usage',
+  'usb',
   'use*',
   'using',
   'usu*',
diff --git a/lib/an.js b/lib/an.js
index a2eb715..d45b97a 100644
--- a/lib/an.js
+++ b/lib/an.js
@@ -1,19 +1,10 @@
 export const an = [
-  'HB',
+  // Please sort these entries.
+  // Please *only* use casing if it adds something: `url` is fine, but it’s
+  // `a UN meeting` and `an un-united germany`.
   'IOU',
   'MA',
-  'MBA',
-  'MRI',
   'MS',
-  'MTV',
-  'RAF',
-  'SGML',
-  'SMS',
-  'SOS',
-  'SPF',
-  'STD',
-  'SUV',
-  'XML',
   'f',
   'fbi',
   'fda',
@@ -28,6 +19,7 @@ export const an = [
   'habitual',
   'hallucin*',
   'hauteur',
+  'hb',
   'heir*',
   'herb*',
   'heredit*',
@@ -47,10 +39,13 @@ export const an = [
   'lbw',
   'lcd',
   'm',
+  'mba',
   'mdast',
   'mpg',
   'mph',
+  'mri',
   'msc',
+  'mtv',
   'n',
   'nba',
   'nbc',
@@ -62,11 +57,19 @@ export const an = [
   'nvidia',
   'r&d',
   'r',
+  'raf',
   's',
+  'sgml',
+  'sms',
+  'sos',
+  'spf',
+  'std',
+  'suv',
   'x',
   'x-ray',
   'x-rays',
   'xbox',
   'xmas',
+  'xml',
   'α'
 ]