Sometimes we wish that we could have more time. The good news is that this year will be longer than the previous! Although don’t get excited just yet, because if you blink (眨眼), you may just miss it. That’s because 2015 will be one second longer than 2014 －also known as a leap second (閏秒). And surprisingly, they are pretty common. But why do we need them?

Over the centuries, Earth has been slowing down. This means that we must keep changing our clocks to keep in step with Earth’s time. We’ve all heard of leap years. Our calendars hold 365 days in a year. Yet Earth takes slightly longer to orbit the sun. So we save this time and every 4 years we have an extra day in February.

As for the leap seconds, the International Earth Rotation Service (IERS) manages the global time, known as the atomic time(原子鐘時(shí)間). This is the timekeeping that’s used for every single country.

To keep up with Earth’s time, they add a second every now and then. They’ve been doing this since 1972. And this year will be the 26th second they’ve added!

It’ll be added just before 8:00 a.m. on July 1 Beijing time. So you will see 7:59:60 on July 1.

Although adding a second sounds harmless, it can have negative effects. In 2012 when a leap second was added, it caused problems for companies like social networking sites Reddit and LinkedIn. As they weren’t prepared for the change, it caused their computers to record errors.

1.Why does a leap second have to be added in some years?

A. Because this year is shorter than the previous one. B. Because we need to have more time.

C. Because the Earth is slowing down. D. Because it can help make a leap year.

2.In a leap year, there is an extra day in_____.

A. January B. February C. March D. December

3.In order to keep up with Earth’s time, how many seconds have been added until last year?

A. 43 B. 42 C. 26 D. 25

4.What’s the negative effect of adding a leap second?

A. It makes the day longer than the previous one. B. It causes some recording errors for companies.

C. It makes people stay up late. D. It does harm to people’s health.

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