1.Adjective as a subject complement: "Schools are instrumental in developing social skills" uses the adjective "instrumental" as a subject complement to describe the role of schools, adding depth to the sentence.
2.Relative clause: "where students can engage in social interactions" uses a relative clause to provide additional information about the "controlled environment," enhancing the complexity of the sentence.
3.Gerund as a subject: "Group activities, for instance, teach teamwork and cooperation" uses the gerund "teaching" as a subject to describe the function of group activities, showcasing advanced grammar usage.
4.Infinitive phrase as an adverbial: "to simulate real-life difficult situations" uses an infinitive phrase to describe the purpose of role-playing exercises, adding clarity and complexity to the sentence.