Sentence:  If you are not well acquainted with the area in which you wish to locate , or if you <WSD>are</WSD> not sure that you and your family will like and make a success of farming , usually you would do better to rent a place for a year or two before you buy . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)