28  Sailing the Course
28.1 A boat shall start, pass each mark on the required side in the correct order, and finish, so that a string representing her track after starting and until finishing would, when drawn taut
(a) pass each mark on the required side,
(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. After finishing, a boat need not cross the finishing line completely.
28.2  A boat may leave on either side a mark that does not begin, bound or end the leg she is on. However, she shall leave a starting mark on the required side when she is approaching the starting line from its pre-start side to start.