set your sights on 狙いを定める

set your sights on something/someone 何かに目標を定める。1:40 Destiny says nothing inappropriate ever took place. but she believe Tad Cummins may have been grooming her before he set his sights on Elizabeth Thomas. 15歳の教え子と恋の逃避行をしたカミンズ容疑者は以前にも教え子のデスティニーちゃんにちょっかいを出していた。デスティニーちゃんはいやらしいことはなかったといっているが、カミンズ容疑者にはエリザベスちゃんに手を出す以前にはデスティニーちゃんを狙っていたようだ。

Teen: I Got The Creeps From Teacher Who Disappeared with 15-Year-Old Student

https://www.youtube.com/watch?v=yZgfboI93Vk  1:07 a slight miscalculation makes no difference. once she set her sights on a target, there's no chance for escape. ちょっとのミスはまったく問題にならない。一度狙った獲物は絶対に逃がさないからだ。
Incredible: A Gaboon Viper Strikes a Bird in Slo-Mo

https://www.youtube.com/watch?v=Ba2KXehUM6o  0:18 this week, the Mercer Report sets its sights and follows the arrow to the 2016 Olympic Games in Rio.
Rick and Archery

https://www.youtube.com/watch?v=4aykAKXtGb0  5:50 but police still have their sights on Lochte and Feigen. この狂言事件でブラジル警察当局はロクテ選手とファーゲン選手の二人を拘束、起訴する方針だ。
US Swimmers Olympic Robbery Bizarre Twists

参考リンク
http://bridge-english.blogspot.jp/2009/07/blog-post_5892.html  目をつけられるを英語でなんと言うか？
http://bridge-english.blogspot.jp/2016/01/blog-post_92.html  お前に決めたを英語でなんと言うか？

練習問題解答
a-6667 our sights are set on
a-9639 he had his sights set on going to NYU
b-1465 setting his sights now on
b-1880 have their sights set on
b-2785 set their sights on
b-3784 set her sights on
b-5856 has his sight set on