The moonball—a high, heavy topspin shot—drives lots of players crazy.

月亮即又高又重的超级上，种让很多员抓狂。

And at the other end, lay one in short – and the point is over, Federer able to flatten it out, or lace it with topspin, the ball exceptionally heavy and often unreturnable.

另方面，费德勒时常能击，在于他能够击出平击或者上，势格外的沉，令人难以回防。