The binding legal principle is that the word "supermarket" in a commercial lease agreement must be interpreted according to its ordinary colloquial meaning as encompassing the entire commercial enterprise, including not only the trading floor area accessible to the public but also all ancillary facilities necessary for conducting the business, such as storage areas, refrigeration facilities, kitchens, and ablution facilities. When interpreting contracts, courts may have regard to the surrounding circumstances and context in which agreements were negotiated, as well as the subsequent conduct of the parties, to ascertain their true intention. The contra proferentem rule is a rule of last resort applicable only where parties have unequal bargaining power and the proper meaning cannot be ascertained through ordinary interpretive methods; it does not apply where agreements were negotiated between parties of relatively equal bargaining strength.