a stock bull的用法和样例：
- A downward tendency, as in the price of a stock.
- A short period of active trading, as on a stock exchange.
- Butter is a stock item for any good grocer.
- A stock of necessary supplies, especially food.
- They bought in(a stock of) coal for the winter.
- We must lay in a stock of more wheat.
a stock bull的相关资料：