An event object is like a switch: it has only two states: on or off.

一个事件对象如同一个开关：它仅有两种状态：开和关。

youdao

In most computerized systems, there are only two states: nonexistence or full-compliance.

多数计算机系统只有两种状态，即不存在或者全部一致。

youdao

The control properties of certain control words (such as bold, italic, keep together, and so on) have only two states.

某个控制字(例如粗体(bold)、斜体(italic)、粗斜体等等)的控制属性仅有两个状态。

youdao

It was also home to the United States Armory and Arsenal, one of only two in the country.

VOA: special.2009.11.06

It passed in the Senate only because two men from slave states voted for it.

VOA: special.2009.03.05

The only time the United States had won more was on its own territory, in two thousand at the Salt Lake City, Utah Winter Games.

VOA: special.2010.02.26

Thus, the law assumes that social media accounts have only two states: personal or not-personal.

FORBES: Big Problems in California's New Law Restricting Employers' Access to Employees' Online Accounts

Before the 2010 election, only two states, Georgia and Indiana, had strict photo-ID requirements in place for voters.

ECONOMIST: Election laws

Only two states, Colorado and Montana are equal minded enough to forbid gender discriminatory pricing by insurers.

FORBES: Gender-Discriminatory Insurance Pricing: I'm Outraged!