In traditional Chinese kitchens, the stove should not have any knives or other cooking utensils hanging over it. In classical fung shui, the stove is associated with the ability of the home's residents to generate wealth. When knife blades point at the stove from above, the occupants will run into obstacles in their professional lives that may compromise their earning capacity. Keep the area above the stove clear. It is inadvisable to eat or drink from bowls, plates, glasses, mugs or cups if they are chipped. Some fung shui masters feel using damaged dishes or vessels will adversely affect one's health, leading to conditions such as heartburn and indigestion. Eating from crockery that is cracked also implies declining financial fortunes. Chopsticks should always be matching. Some masters say using mismatched chopsticks may lead to a complicated love life. Also, chopsticks should never be stuck apart vertically into a bowl of rice. This evokes two joss sticks protruding from an urn at worship and is also how chopsticks are placed when food offerings are made to ancestors. Replicating this yin pattern (associated with praying and the spiritual world) in a yang situation (when dining with others) is offensive as it may be interpreted as beckoning yin energies.