If there is no year element, then the call will return null.

如果没有year元素，则调用返回一个空值。

youdao

The following functions return the day of Thanksgiving for a given year. If no year is given then current year is used.

下面这个函数将返回给定年份感恩节的日期。如果没有指定年份，就计算当年的。

youdao

The impact of sluggish 3 growth on year-end payouts may have peaked in 2015, however, when 66 per cent of white-collar workers received no year-end bonus.

不过，增长疲软对年终奖的影响或许在2015年已见顶。当时，66%的白领员工没有收到年终奖。

youdao

But he says only one or two students usually choose it each year, and no one did in the graduating class in May.

VOA: special.2009.07.23

And we graduated the same year -- now no one has to say what year that was, even if you know, but we did graduate the same year.

我们同一年毕业的-,当然我不要求你们说出是哪一年，可能有人知道，我们在同一年毕业。

麻省理工公开课 - 化学原理课程节选

So we have--U.S. Government issues bills and that's less than or equal to one year and they pay no interest.

美国政府发行的短期国库券,期限通常小于或等于一年,且不付息

耶鲁公开课 - 金融市场课程节选

Even during the 2000--01 recession their absolute revenues increased: In no year since 2000 have those revenues actually declined.

FORBES: Fact and Comment

And there was no year-over-year change in the churn rate for iPhone customers.

FORBES: D9: AT&T Mobility CEO De La Vega Defends The T-Mobile Deal

Since 1990 there was no year in which the Romneys did not owe federal and state income taxes .

FORBES: Romney Accountant's Letter - Exercise In Obfuscation ?