她原先的投资已经增加到两倍。

Her original investment has increased twofold.

这一数字意味着生产提高了两倍。

This figure means a twofold increase in production.

新驾驶员所出的事故是老驾驶员的两倍。

New drivers have twice as many accidents as experienced drivers.

在过去的两年里，食物中毒事件增加了两倍。

Cases of food poisoning have trebled in the last two years.

在这个行业，女性人数是男性的两倍。

In this profession, women outnumber men by two to one.

这个房间的长度是厨房的两倍。

This room is twice the length of the kitchen.

他们正以两倍于法定限速的速度行驶。

They were travelling at a speed that was double the legal limit.

我们需要现有数量的两倍。

We need double the amount we already have.

他在两年间收入增加了两倍。

He trebled his earnings in two years.

这架飞机的速度将是音速的两倍。

The aeroplane will travel at twice the speed of sound.