Merge pull request #208 from ekcom/fix/more-background-corrections

Small fixes on Background page

background/background.tex

@@ -220,7 +220,7 @@ \subsection{Editors}
 You enter vim by typing \keyword{vim [file]}, which takes you into the editor.
 There are three most commonly used modes: normal mode, insert mode, and command mode.
 You start off in normal mode.
-In this mode, you can move around with many keys with the most common ones being \keyword{hjkl} (corresponding to left, down, up, and right respectively).
+In this mode, you can move around with many keys with the most common ones being \keyword{hjkl} (corresponding to left, down, up, and right, respectively).
 To run commands in vim, you can first type \keyword{:} and then a command after it.
 For instance, to quit vim, simply type \keyword{:q} (q stands for quit).
 If you have any unsaved edits, you must either save them \keyword{:w}, save and quit \keyword{:wq}, or quit and discard changes \keyword{:q!}.
@@ -658,8 +658,8 @@ \subsection{Clang Static Build Tools}
 
 \subsection{strace and ltrace}
 
-strace and ltrace are two programs that trace the system calls and library calls respectively of a running program or command.
-These may be missing on your system so to install feel free to run the following.
+strace and ltrace are two programs that trace the system calls and library calls, respectively, of a running program or command.
+These may be missing on your system, so to install, run the following:
 
 \begin{lstlisting}[language=bash]
 $ sudo apt install strace ltrace
@@ -845,7 +845,7 @@ \subsection{Watch the videos and write up your answers to the following question
 \url{http://cs-education.github.io/sys/}
 
 Questions? Comments? Use the current semester's CS341 Edstem:
-\url{https://edstem.org/us/courses/41378/discussion/}
+\url{https://edstem.org/us/courses/61021/discussion/}
 
 The in-browser virtual machine runs entirely in JavaScript and is fastest in Chrome.
 Note the VM and any code you write is reset when you reload the page, \textbf{so copy your code to a separate document.}