--- a/testing/web-platform/tests/web-animations/interfaces/KeyframeEffect/processing-a-keyframes-argument.html
+++ b/testing/web-platform/tests/web-animations/interfaces/KeyframeEffect/processing-a-keyframes-argument.html
@@ -179,84 +179,86 @@ test(() => {
     {done: false, value: {left: '200px'}},
     {done: true},
   ]));
   assert_frame_lists_equal(effect.getKeyframes(), [
     {offset: null, computedOffset: 0, easing: 'linear', left: '100px'},
     {offset: null, computedOffset: 0.5, easing: 'linear', left: '300px'},
     {offset: null, computedOffset: 1, easing: 'linear', left: '200px'},
   ]);
-}, 'Custom iterator with basic keyframes.');
+}, 'Keyframes are read from a custom iterator');
 
 test(() => {
   const keyframes = createIterable([
     {done: false, value: {left: '100px'}},
     {done: false, value: {left: '300px'}},
     {done: false, value: {left: '200px'}},
     {done: true},
   ]);
   keyframes.easing = 'ease-in-out';
   keyframes.offset = '0.1';
   const effect = new KeyframeEffect(null, keyframes);
   assert_frame_lists_equal(effect.getKeyframes(), [
     {offset: null, computedOffset: 0, easing: 'linear', left: '100px'},
     {offset: null, computedOffset: 0.5, easing: 'linear', left: '300px'},
     {offset: null, computedOffset: 1, easing: 'linear', left: '200px'},
   ]);
-}, 'easing and offset are ignored on iterable objects.');
+}, "'easing' and 'offset' are ignored on iterable objects");
 
 test(() => {
   const effect = new KeyframeEffect(null, createIterable([
     {done: false, value: {left: '100px', top: '200px'}},
     {done: false, value: {left: '300px'}},
     {done: false, value: {left: '200px', top: '100px'}},
     {done: true},
   ]));
   assert_frame_lists_equal(effect.getKeyframes(), [
     {offset: null, computedOffset: 0, easing: 'linear', left: '100px', top: '200px'},
     {offset: null, computedOffset: 0.5, easing: 'linear', left: '300px'},
     {offset: null, computedOffset: 1, easing: 'linear', left: '200px', top: '100px'},
   ]);
-}, 'Custom iterator with multiple properties specified.');
+}, 'Keyframes are read from a custom iterator with multiple properties'
+   + ' specified');
 
 test(() => {
   const effect = new KeyframeEffect(null, createIterable([
     {done: false, value: {left: '100px'}},
     {done: false, value: {left: '250px', offset: 0.75}},
     {done: false, value: {left: '200px'}},
     {done: true},
   ]));
   assert_frame_lists_equal(effect.getKeyframes(), [
     {offset: null, computedOffset: 0, easing: 'linear', left: '100px'},
     {offset: 0.75, computedOffset: 0.75, easing: 'linear', left: '250px'},
     {offset: null, computedOffset: 1, easing: 'linear', left: '200px'},
   ]);
-}, 'Custom iterator with offset specified.');
+}, 'Keyframes are read from a custom iterator with where an offset is'
+   + ' specified');
 
 test(() => {
   assert_throws({name: 'TypeError'}, function() {
     new KeyframeEffect(null, createIterable([
       {done: false, value: {left: '100px'}},
       {done: false, value: 1234},
       {done: false, value: {left: '200px'}},
       {done: true},
     ]));
   });
-}, 'Custom iterator with non object keyframe should throw.');
+}, 'Reading from a custom iterator that returns a non-object keyframe'
+   + ' should throw');
 
 test(() => {
   const effect = new KeyframeEffect(null, createIterable([
     {done: false, value: {left: ['100px', '200px']}},
     {done: true},
   ]));
   assert_frame_lists_equal(effect.getKeyframes(), [
     {offset: null, computedOffset: 1, easing: 'linear'}
   ]);
-}, 'Custom iterator with value list in keyframe should not contain invalid ' +
-   'property value pair of list.');
+}, 'A list of values returned from a custom iterator should be ignored');
 
 test(function(t) {
   const keyframe = {};
   Object.defineProperty(keyframe, 'width', {value: '200px'});
   Object.defineProperty(keyframe, 'height', {
     value: '100px',
     enumerable: true});
   assert_equals(keyframe.width, '200px', 'width of keyframe is readable');