28.1 A boat shall start, sail the course described in the sailing instructions and finish. While doing so, she may leave on either side a mark that does not begin, bound or end the leg she is sailing. After finishing she need not cross the finishing line completely.

28.2 A string representing a boat’s track from the time she begins to approach the starting line from its pre-start side to start until she finishes shall, when drawn taut,
(a) pass each mark on the required side and in the correct order,
(b) touch each rounding mark, and
(c) pass between the marks of a gate from the direction of the previous mark.
She may correct any errors to comply with this rule, provided she has not finished.