Add "modality" to single pointer definition with examples of single pointer interactions

guidelines/terms/21/single-pointer.html

@@ -1,6 +1,6 @@
 <dt><dfn id="dfn-single-pointer">single pointer</dfn></dt>
 <dd>
-   <p>an input that only targets a single point on the page/screen at a time – such as a mouse, single finger on a touch screen, or stylus.</p>
-   <p class="note">In contrast to single pointer inputs, multipoint interactions involve the use of two or more pointers at the same time – such as two finger interactions on a touchscreen, or the simultaneous use of a mouse and stylus.</p>
+   <p>an input modality that only targets a single point on the page/screen at a time – such as a mouse, single finger on a touch screen, or stylus.</p>
+   <p class="note">Single pointer interactions include clicks, double clicks, taps, dragging motions, and single-finger swipe gestures. In contrast, multipoint interactions involve the use of two or more pointers at the same time, such as two finger interactions on a touchscreen, or the simultaneous use of a mouse and stylus.</p>
 </dd>