Dưới đây là các từ có thể điền vào chỗ trống:

(7) **support**
(8) **carefully**
(9) **positive**
(10) **lifetime**

Nội dung hoàn chỉnh sẽ là:

"Having friends who are kind and understanding can boost a teenager’s confidence. However, it’s also important to choose friends carefully. Sometimes, negative friendships can lead to peer pressure. Teens should surround themselves with friends who encourage positive behavior and healthy choices. By building strong friendships, teenagers can create a support network that lasts a lifetime."