Pear trees

Question

my pear tree is four years old, and has never flowered or born fruit?

Answer 1

Most fruiting pear trees need a pollinator to bear fruit, meaning another variety of fruiting pear. Ornamental pear trees just don't bear fruit, or very rarely do. So depending on what type of pear it is, one of these is probably the problem.
This article may help:
https://www.gardeningknowhow.com/edible/fruits/pear/pear-tree-pollination.htm