“我打籃球打得跟網球一樣好” 的英語通常會怎麼說比較合適?

as well as 是一個俗語. 是"也..." 或是 "一樣"的意思. 也喪失了 "...好..."的意思.

I play basketball as well as tennis. 只有＂我玩籃球　也玩網球＂而沒有　＂一樣好＂的意思．甚至沒有＂好＂的意思．

若要說＂一樣好＂，請用：

I play both basketball and tennis well.

as well as不是同樣的好，而是"同時"或"一起"

你的句子I play basketball as well as play tennis.英語人看來的意思是「我會打籃球又會打網球」=我兩種球類都懂。

假如你只想用"well"來表達你"打得很好"，便只能說：
I play basketball and tennis equally well.

但假如你要想用...as... as這句子結構來表達"打得同樣的好/棒"，便只能說：
I play basketball as good as tennis. [留意後段不同再加play，因為仍是你做的動作]

I play basketball as good as tennis. Yip