Monohybrid is the crossing of two organisms that differ from each other in one pair of alternative (mutually exclusive) characters.
Crossbreeding is called dihybrid, in which inheritance is considered and the offspring are accurately quantified for two pairs of alternative characters, or rather, for mutually exclusive variants of these characters.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.