This once-in-alifetime ?event actually may take ?place twice in some folks’ lives.

Get key information by reading just once or twice.

A letter written by Charles Darwin in 1875 has been returned to the Smithsonian Institution (檔案館) by the FBI after being stolen twice.

As a guest flyer, the king worked about twice a month, always as co-pilot.

Experimental users may try drugs once or twice.

since then, I have been trying to attend dancing classes twice a week after work.

Some raised more than twice their goals, but others have fallen short of reaching even modest targets.

That's the conclusion of a new study that finds that Earth's oceans now 26 absorb heat at twice the rate they did 18 years ago.

This once-in-a-lifetime event actually may take place twice in some folks' lives.

It is also troubling that voting rates among our youngest eligible voters—18- to 24-year-olds—are way down: Little more than one in four now go to the polls, even in national elections, compared with almost twice that many when 18-year-olds were first given the vote.

Enrollees would have to pay more money for many services out of their own pockets, and that would encourage them to think twice about whether an expensive or redundant test was worth it.

Piling on higher taxes won't help, "If higher taxes make it more expensive to raise children," says Nicholas Eberstadt of the American Enterprise Institute, "people will think twice about having another child.

To advise couples to think twice before having children

The stack of congressional regulations governing federal student grants and loans now stands twice as tall as I do.

Since 1982 tuitions have been rising at roughly twice the rate of inflation.

But over the next few decades labour forces in rich countries are set to shrink so much that inflows of immigrants would have to increase enormously to compensate: to at least twice their current size in western Europe's most youthful countries, and three times in the older ones.

That same study found that randomly assigned interracial roommates at Ohio State broke up before the end of the quarter about twice as often as same-race roommates.

After six months, researchers found the high protein group had significantly improved their muscle function一almost twice as much as the control group.

It is also troubling that voting rates among our youngest eligible voters—18- to 24-yearolds— are way down: little more than one in four now go to the polls, even in national elections, compared with almost twice that many when 18-year-olds were first giv

Older adolescents scored about 50 percent higher on an index of risky driving when their peers were in the room — and the driving of early adolescents was fully twice as reckless when other young teens were around.

The European Union's level of international co-authorship is about twice that of the United States, Japan, and India.

The extreme isolation of these massive farms leaves them often unattended, and monitored only once or twice a year, which means if the livestock falls ill or requires assistance, it can be a long time for farmers to discover.

They cited a study presented earlier this year of 249 pairs of parents and their children in which twice as many children as parents wanted rules on what parents could share.

This is more than twice the level of two decades ago.

Those who used such devices 40 hours a week or more one in ten teenagers were twice as likely to be unhappy.

While some economists predict continued recovery in the future, Baily says the only certainty is that banks are unlikely to make the same mistakes twice.

Americans eat only about fifteen pounds of fish per person per year, but we eat twice as much fish in restaurants as at home.

Several safari camps operate as the base for this adventure, providing unique rides twice a day to explore deep into the delta.

The obvious one is money: eating out once or twice a week may be affordable but doing this most days adds up.

Those who had done the most boyhood activities were twice as likely to have warm relations with a wide variety of people, five times as likely to be well paid and 16 times less likely to have been unemployed.

Think twice before we act.

During the decade before the economic crisis, spending on legal services in America grew twice as fast as inflation.

Getting the print edition seven days a week costs $500 a year—more than twice as much as a digital-only subscription.

After bills, Tony has ￡60 a week to spend, ￡40 of which goes on food, but 10 years ago he was earning ￡130,000 a year working in corporate communications and eating at London's best restaurants at least twice a week.

There has been a kind of inflationary process at work: ?nowadays anyone applying for a research post has to have published twice the number of papers that would have been required for the same post only 10 years ago.

Today, because of shrewd advertising and public health campaigns, many Americans habitually give their pearly whites a cavity-preventing scrub twice a day, often with Colgate, Crest or one of the other brands.