searching a file provided for key words provided and printing the number of times it has been found.

week3challenge.sh

#!/bin/bash
# give counts for two different variables
# for any file passed
# and output the values
n1=`grep -i $1 $3 | wc -l`
n2=`grep -i $2 $3 | wc -l`

# output the values
echo In file: $3
echo I found $1 $n1 times
echo I found $2 $n2 times

What happens if I run the file with the wrong number of arguments?
$./week3challenge.sh yay example.csv
Can you add error checking to make sure the appropriate number of arguments have been given?