acceleration
n[U]
1 making or being made quicker; increase in speed 加快; 促进; 加速
an acceleration in the rate of economic growth 经济发展速率的增长.
2 (of a vehicle) ability to gain speed (指车辆)加速性能
a car with good acceleration 加速性能良好的汽车.
Mathilde! I've got some wonderful news. We've been invited to the ball at the palace.
玛蒂尔德!我有一个极好的消息。我们被邀请去参加宫庭舞会。
My dear friend, Mathilde. Let me tell you something. That necklace you borrowed from me wasn't a real diamond necklace. It wasn't valuable at all. The stones in the necklace were made of glass. It was worth five hundred francs at the most.