docs: typos

Signed-off-by: Yukai Chou <muzimuzhi@gmail.com>

Author: muzimuzhi

doc/generic/pgf/pgfmanual-en-tikz-paths.tex

@@ -302,7 +302,7 @@ \subsubsection{Horizontal and Vertical Lines}
     \index{--2@\protect\texttt{\protect\pgfmanualbar-} path operation}%
     \index{Path operations!--2@\protect\texttt{\protect\pgfmanualbar-}}%
     \pgfmanualpdflabel[\catcode`\|=12 ]{|-}{}%
-    This operations means ``first vertical, then horizontal''.
+    This operation means ``first vertical, then horizontal''.
 \end{pathoperation}
 }
 
@@ -601,10 +601,10 @@ \subsection{The Grid Operation}
 You can add a grid to the current path using the |grid| path operation.
 
 \begin{pathoperation}{grid}{\opt{\oarg{options}}\meta{corner or cycle}}
-    This operations adds a grid filling a rectangle whose two corners are given
+    This operation adds a grid filling a rectangle whose two corners are given
     by \meta{corner} and by the previous coordinate. (Instead of a coordinate
     you can also say |cycle| to use the position of the last move-to as the
-    corner coordinate, but it not very natural to do so.) Thus, the
+    corner coordinate, but it is not very natural to do so.) Thus, the
     typical way in which a grid is drawn is |\draw (1,1) grid (3,3);|, which
     yields a grid filling the rectangle whose corners are at $(1,1)$ and
     $(3,3)$. All coordinate transformations apply to the grid.