grammer Problem(Too easy)

I think Nicole usually talks with her friends at the weekend. I think Mark goes to visit the elderly people at the weekend . I think Mable usually reads with her friends in the library at the weekend. (以上的句子基本上正確)
這句須修改成：I think Charlie usually plays (sports games )with his friend at the weekend.

但你亦可將句子中的 (at the weekend )改成 (at weekends)(表示通常會在週末做....)

我會寫成:

I think Nicole usually talks to her friends at weekends. I think Mark goes visit the elderly people at weekends. I think Mable usually reads with her friends in the library at weekends. I think Charlie usually play sport games with his friends at weekends. Is there any problem?