例句：
The central bank should also serve as as a lender of last resort to the money market.
中央银行应该在金融市场中扮演最终贷款人的`角色。
PHP has an array type that doubles as as a simple list and a dictionary or hash; Python separates the two.
PHP的数组类型可同时支持简单列表和字典或散列，但Python却将这两者分开。
Think of it as as if you were buying an expensive car: a test drive is crucial before making a final decision.
例如，你想买一辆高级轿车，下决心前的试验驾驶就是至关重要的。