Travel Information Section on Visa Form

My family is travelling to Hongkong in July and planning to visit China as well, but haven't decided on a destination yet. We will join a tour in Hongkong. In this case, under the Travel Information section, is it possible just to put down the city and dates we intend to visit e.g. Guangzhou, end of July? Kindly please advise of the correct way to do this entry. Thank you.