【2题详解】

细节理解题。根据They compared how accurately participants read those facial expressions using their particular eye movement strategies.可知，在研究中，人们被要求对一些脸部照片进行分类。故选C。

【3题详解】

细节理解题。根据上下文可知指的是参与者，可知，"they"指代的是研究参与者。故选A。

【4题详解】

细节理解题。根据Easterners use the eyes more可知，与西方人相比，东方人可能更注意观察眼睛。故选 C。

　　He may not have an "S" across his chest but this dog is most certainly a hero.

　　Harley, who was rescued from a puppy mill four years ago, was named the American Humane Association's 2015 American Hero Dog. Harley, who is missing an eye and has other medical issues from his time at the mill, is now a "spokes-dog" against puppy mills. He serves as the adorable furry face of the "Harley to the Rescue" campaign, which raises funds for the National Dog Mill Rescue, according to a press release.

　　The pup was rescued back in 2011 and adopted by Rudi and her husband, Dan. "It was just four years ago that he was pulled from the cage in the puppy mill and left to die," Harley's owner, Rudi, said during the awards show at the Beverly Hilton Hotel in Los Angeles this past weekend, according to Today. com. "We never would have ever thought he would live this long and make such a difference for so many puppies."

　　The dog was one of eight finalists up for the American Hero Dog and was chosen as the winner through public votes. The finalists all won $ 1,500 to be donated to one of American Humane Association's charity partners, with Harley receiving another $ 5 ,000 to go toward his charity partner, New Leash On Life.

　　According to the release, Harley spent 10 years at the puppy mill, and endured rough treatment there, which led to his many medical issues. He lost his eye as a result of his cage being power-washed with him inside.

The dog isn't just the face of his campaign, he also goes on rescue missions and makes public appearances at events and schools to raise awareness for puppy mills.