What's wrong with hybrid rice? What is the principle? What should we say simply and clearly?

High school biology told me that hybrid rice is hybrid and the principle is gene recombination. The law of free combination of genes is one of the laws of gene recombination.

Mendel's law of free combination of genes can combine excellent characters in a variety. For example, Aa and Bb determine a pair of shapes, which do not interfere with each other. A and B are excellent roles. Parents' genotypes are aaBB and AAbb, so the genotype of offspring can be obtained through hybridization, so his phenotype is two excellent traits. Of course, the production process of hybrid rice is extremely complicated, which was obtained by China researchers after years of unremitting struggle. High school biology is just a scratch. So we should cherish food.