What is the main of this passage?
if you've ever tasted homemade jam, you know the delicious rewards canning can bring. although it is fun and fulfilling, canning is not an easy task. first of all, you need to grow or buy fresh fruit and wash it carefully. then the clean fruit has to be mashed, heated to a boil, and mixed with sugar and pectin to get it to gel. once the fruit is ready, it must be poured carefully into clean, hot glass jars. next, add a lid and submerge the jars in a boiling water bath for about 10 minutes. as they cool, the "pop" of the lids tells you they have sealed.
a. if the lid doesn't "pop," the jar is not sealed properly.
b. the jars used for canning must be hot as well as clean.
c. in addition to fruit, you can also can many vegetables.
d. canning is fun, but it takes a lot of work and knowledge.