--- title: Growing up: ages of people and pets, and the "dog years" myth — a lesson of Mova's school · trees and pragmatics description: «Growing up: ages of people and pets, and the "dog years" myth», a lesson of the world course of Mova's primary school, sentence by sentence with dependency trees and pragmatics. It begins: Living things age at very different speeds. --- [Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/) [home](https://md.mova.elamur.ai/free/en/) / [corpora](https://md.mova.elamur.ai/free/en/corpora/) / [school](https://md.mova.elamur.ai/free/en/corpora/school/) / [World](https://md.mova.elamur.ai/free/en/corpora/school/world/) / Growing up: ages of people and pets, a… # Growing up: ages of people and pets, and the "dog years" myth Lesson 128 of the world course of Mova's primary school: 21 sentences, each with its syntax tree and pragmatics. The lessons are written for Mova, and their agreed trees are part of Mova corpus 0.4 (CC BY-SA 4.0). How Mova does on its tests: [the lesson at school](https://md.mova.elamur.ai/free/en/school-run/world/128-growing-up-ages-dog-years/). - [0](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/0/) — Living things age at very different speeds. - [1](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/1/) — A hamster is old at 2; a mayfly lives only about a day as a flying adult, after a year or more as a nymph underwater; a cat often lives 12 to 18 years; and a tortoise can outlive its owner's whole family: Jonathan, on the island of St Helena, is thought to have hatched around 1832. - [3](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/3/) — Dogs grow up very fast at first, so a 1-year-old dog is already like a teenager, and then they age more slowly; big dogs age faster than small ones. - [4](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/4/) — A vets' guide for a middle-sized dog says year 1 is like about 15 human years, year 2 brings it to about 24, then add about 5 for each year after: a 3-year-old dog is like about 28 or 29, not 21. - [5](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/5/) — Cats work the same way with 4 a year after the second: a 10-year-old cat is like a person of about 56, middle-aged. - [6](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/6/) — Children grow at their own speeds, often about 5 to 6 cm a year before puberty (when a child's body starts changing into a grown-up's), with growth spurts that come especially in the teens; sleep, food and play all help. - [7](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/7/) — You can guess with a simple sum: 20 cm to go at 5 cm a year takes 4 years. - [8](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/8/) — Bodies keep time too: a child's heart beats about 80 times a minute, a mouse's about 500 and an elephant's about 30. - [9](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/9/) — Growing up brings new things you're allowed to do, like learning to drive at 17 in Britain, but being on time stays your job all your life. - [10](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/10/) — The old "times 7" rule for dog years is a myth. - [11](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/11/) — A vets' guide for a middle-sized dog: the first year is like about 15 human years, by the second year about 24, then about 5 more for each year after. - [13](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/13/) — For cats the first year is like about 15, the second brings it to about 24, then about 4 a year, so a 10-year-old cat is like about 24 + 8 × 4 = 56. - [14](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/14/) — Cats often live 12 to 18 years, and hamsters about 2 to 3 years. - [15](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/15/) — Some tortoises live over 100 years; Jonathan, on St Helena, is thought to have hatched around 1832, about 194 years before 2026. - [16](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/16/) — An adult mayfly lives about a day, after a year or more as a nymph underwater. - [17](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/17/) — Children often grow about 5 to 6 cm a year before puberty, and growth spurts happen, especially in the teen years. - [18](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/18/) — Holly, 140 cm, growing about 5 cm a year, needs 20 ÷ 5 = 4 years to reach 160 cm. - [19](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/19/) — A child's heart beats about 80 times a minute, which is 80 × 60 = 4,800 times an hour. - [20](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/20/) — Small animals' hearts usually beat faster: a mouse's can beat about 500 times a minute and an elephant's about 30. - [21](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/21/) — 10 is the first age with two digits. - [22](https://md.mova.elamur.ai/free/en/corpora/school/world/128-growing-up-ages-dog-years/22/) — In Britain you can start learning to drive a car at 17. - ← previous: [Sleep and the body clock](https://md.mova.elamur.ai/free/en/corpora/school/world/127-sleep-and-the-body-clock/) - next →: [Being on time around the world, waiting your turn and deadlines](https://md.mova.elamur.ai/free/en/corpora/school/world/129-being-on-time-around-the-world/) - ↑ back to [World](https://md.mova.elamur.ai/free/en/corpora/school/world/)