axis of spin的用法和样例：
- A gyroscope is so mounted that, as its axis of spin establishes and maintains the true vertical, it makes possible the establishment of a reference plane in the horizontal.
- The axis of a circle is its diameter.
- He put a lot of spin on his backhand return.
- There was a lot of spin on that ball.
- The main axis of a compound leaf.
- He put a lot of spin on his backhand re-turn.