Programming :: How Sed Can Catch Variable From Input?

right now i am writing bash script for simple everyday todo tasks.script consisit of two files, fisrt is just script (which can delete/append /clear) and second one is todolist.txt which stores my notes.I am litlebit confused about sed!!for example, If my todolist.txt have these lines:

- Writing my Homework
- take my girlfriend to launch
- Take a break

How can sed take my input $@ and delete all line with name "Homework"..i trayed with many sed combination like:

Code:
sed s/$@//g
sed 'd/$@/'
and many more combination with ""/'' or bracket but nothing helped