Calf, Baby Cow
noun
You have a child cow. What do you think a child cow is? Probably a calf or a baby cow.
こうし
Since you should know the readings of the words 子 and 牛 from the previous level, you should be able to read this word too even though it's using the kun'yomi readings for the kanji.
この子牛は、まだまだ小さい赤ちゃんです。
This calf is still a little baby.
とても元気な子牛が生まれたよ。
A very healthy calf was born.
サンタさん、どうか子牛をプレゼントして下さい。
Dear Santa Claus, please bring me a calf as a present.