Write a reaction (a single reaction, an overall reaction, if you like, for the reaction of chlorine gas with methane to produce carbon tetrachloride. When I say a single reaction, I mean use a single arrow. You answer will look like this:
CH4 + x Cl2 - - - > CCl4 + y HCl
So, to make this a correct answer (on your assignment) you need to draw all bonds in all of the compounds (always) and then include the right value for x and y.
Do the same for creating chloroform (CCl3). This reaction will differ from that above only in the identify of the product and then in the value of x and y. Hint: x (or y for that matter) does not have to be an integer in chemical equations when balancing them.