I also write in my diary.

我也写日记。

I also like Beijing Opera.

我也喜欢京剧。

Can I also be his pen pal?

我也可以做他的笔友吗？

I also have a healthy diet.

我也有一个健康的饮食。

I also like playing tennis.

我也喜欢打网球。

I also want to go to the park.

我还想去公园。

I also read books about birds.

我还读了关于鸟的书。

I also want to buy some books.

我还想买些书。

I also go swimming on Saturdays.

我还在星期六去游泳。

I also have an eraser and a ruler.

我还有一块橡皮和一把尺子。