diff --git a/test/test.js b/test/test.js
index 82cde29..980f528 100644
--- a/test/test.js
+++ b/test/test.js
@@ -1,9 +1,13 @@
 const tape = require('tape')
 const cutls = require('../dist/cutls')
 
-tape('Strings module tests', function (test) {
-  test.equal(cutls.strings.capitalizeWord('hello'), 'Hello')
-  test.equal(cutls.strings.capitalizeWords('hello world'), 'Hello World')
-  test.deepEqual(cutls.strings.capitalizeWordList(['hello', 'world']), ['Hello', 'World'])
+/** String module tests **/
+
+tape('Capitalize functions', function (test) {
+  test.equal(cutls.strings.capitalize('hello'), 'Hello')
+  test.deepEqual(cutls.strings.capitalizeList(['hello', 'world']), ['Hello', 'World'])
+  test.throws(() => cutls.strings.capitalize(1))
+  test.throws(() => cutls.strings.capitalize(true))
+  test.throws(() => cutls.strings.capitalizeList(['hello', 1]))
   test.end()
 })