improve wording

Author: vladak

intro.tex

@@ -2360,7 +2360,7 @@
 \item The \emsl{\emph{context}} is the memory of a process, register contents and
 the kernel data structures relevant to that process.
 \item In other words -- the context of a process is its state. When the system
-is executing the process, one says that it runs in the process context.
+is executing the process, one says that it is running in the process context.
 The classic kernel handles interrupts in the context of an interrupted process.
 \item The threads were introduced to UNIX later - originally there were just
 processes that from today's perspective had only a single thread. The