Even if all goes well for you in high school, that time of life still can be tough. After all, there's so much for you(learn) academically and socially, like getting along with classmates, and dealing with teachers. But of all the(challenge), making good friends might be the most important. According to a new study published in the journal Child Development, best friends likely had a(significance) influence on how you behave in your 20s. Researchers found that those with strong and close bonds with their friends at age fifteen were more likely to be healthy and happy later. Importantly, (popular), defined as lots of people liking you generally but not closely, wasn't found to have the same benefit as close friends. The University of Virginia researchersran the study followed 169 subjects aged 15 to 25 every year for a decade. Then the researchers(analyze) the 10 years of data to understand how people handled stress over time. They found that, compared to people with strong high school friendships, those who were merely popular did much (bad) on several measures of mental health, such as self-worth, social acceptance and relaxation. "(like) by a large group of people cannot takeplace of building deep, supportive friendships. So trying to build close connectionsfew people should be a priority(优先考虑的事情), "wrote Joseph Allen, who coauthored the study.