So it's just a single, quick flap of the tongue.

所以这只是一次快速的舌头拍动。

Flap T. Double T, a single flap T, because the T sound comes between two vowels.

Flap T. Double T，单瓣T，因为T音出现在两个元音之间。

And then there's a single flap of the tongue against the roof of the mouth for the T.

然后是 T 的舌头单瓣抵住上颚。