In butterfly both the arms move together like this, and when you want to breathe, your head comes up as your arms push through the water, and then goes back down on the recovery.

蝶泳时，两臂是同时运动的，当你想呼吸时，你的头在手臂推水的同时漏出水面呼吸，然后回到水面以下。

youdao

In butterfly both the arms move together like this, and when you want to breathe, your head comes up as your arms push through the water, and then goes back down on the recovery.

蝶泳时，两臂是同时运动的，当你想呼吸时，你的头在手臂推水的同时漏出水面呼吸，然后回到水面以下。

youdao