docs: v.kernel.html minor edits

vector/v.kernel/v.kernel.html

@@ -1,11 +1,10 @@
 <h2>DESCRIPTION</h2>
 
 <em>v.kernel</em> generates a raster density map from vector points
-data using a moving
-kernel. Available <a href="https://en.wikipedia.org/wiki/Kernel_(statistics)#Kernel_functions_in_common_use">kernel
+data using a moving kernel. Available <a href="https://en.wikipedia.org/wiki/Kernel_(statistics)#Kernel_functions_in_common_use">kernel
 density functions</a> are <em>uniform, triangular, epanechnikov,
-quartic, triweight, gaussian, cosine</em>, default
-is <em>gaussian</em>.
+quartic, triweight, gaussian, cosine</em>. The default function is <em>gaussian</em>.
+
 <p>The module can also generate a vector density map on a vector network.
 Conventional kernel functions produce biased estimates by overestimating
 the densities around network nodes, whereas the equal split method of

vector/v.to.3d/v.to.3d.html

@@ -6,17 +6,19 @@ <h2>DESCRIPTION</h2>
 parameter.
 
 <p>
-Flag <b>-r</b> enables to perform reverse transformation, i.e.,
-transform 3D vector to 2D by omitting z-coordinate. Height of input 3D
+The flag <b>-r</b> enables to perform reverse transformation, i.e.,
+transform 3D vector to 2D by omitting z-coordinate. The height of input 3D
 features can be optionally stored in <b>column</b>.
 
 <h2>NOTES</h2>
 
+<p>
 When transforming 2D vector features to 3D based on attribute, all
 NULL values are silently converted to height 0.0.
+
 <p>
-Reverse transformation is possible for points and lines.
-In case of lines, the reverse transformation should be used
+The reverse transformation, 2D to 3D, is possible for points and lines.
+In the case of lines, the reverse transformation should be used
 only when all vertices of a line have the same z-coordinate
 (for example contours).