1. Put the colander over the mixing bowl. Empty the chicken or turkey into the colander so the liquid drains into the bowl. Throw away the liquid. Put the chicken or turkey into the bowl. Break up the meat using the fork.
2. On the cutting board, use the sharp knife to cut the cucumber in half. (Wrap half of the cucumber in plastic wrap and refrigerate to use another time.) Cut the end from the remaining cucumber half. Throw away the end. Cut the remaining cucumber lengthwise in half. Place the 2 pieces flat on the cutting board. Chop each piece into small pieces.
3. Add the cucumber, cheese, and salad dressing to the chicken or turkey. Stir with the fork to mix.
4. Spoon one-fourth of the chicken mixture near one edge of one tortilla. Top with one-fourth of the lettuce. Fold the edge nearest the filling over the filling just till it is covered. Then, roll up the tortilla. Repeat 3 more times to make 4 burritos.