I sharpened my skills under the mentorship of my coach.
You need a noun to complete this sentence, and mentorship is the only noun here - the rest of the words are adjectives.
It's describing "cookies" which is a noun which makes it an adjective phrase, because adjectives describe nouns :)
Explanation:
Name the device that is Used to measure the depth of ocean or sea
There are many different types of animals there, each with its own purpose. Come and learn about why there are animals on farms, as well as specific facts about cows, chickens and pigs.