a left-arm spin bowler的用法和样例：
- He had his left arm injured trying to save a comrade.
- Is an arm signal for a left turn made by extending the left arm straight out of the window?
- He has a bullet wound in the left arm.
- A black mole on her left arm remarks her.
- His left arm was hurt in an accident.
- She made a signal with her arm for a left turn.