You should brush your teeth at least once a day.

She has to mop the kitchen floor at least once a day.

她至少每天擦一次厨房的地板.

And they are only given food once a day.

而且它们一天只吃一次东西.

At least 60% of us now bathe or shower once a day.

现在我们当中至少60%的人每天淋浴或洗澡一次。

And close your eyes, And smile at least once a day!

然后闭上你的双眼, 记住每天至少微笑一次!

Walking at least once a day, each about half an hour.

每天至少散步一次, 每次大约半个小时.

It'should be done at least once a day, before brushing.

每天至少使用一次, 在刷牙之前.

Each student has to hand in a composition once a week.

每个学生每周必须交一篇作文.

In the ordinary course of events, I visit her once a week.

在一般情况下, 我每周去看她一次.

Slough off dry skin once a week.

每周除一次干皮.

Of course, I'll visit at least once a year, maybe more.

当然, 我最少每年会来拜访一次, 也许更多次.

Once a year a race is held for old cars.

每年举行一次旧汽车比赛.

Serpents cast their skin once a year.

蛇每年蜕一次皮.

The Moon reaches its absolute perigee once a year.

月球每年有一次达到它的绝对近地点.

Once a year they have to flush the city's sewers.

每年,他们都得冲洗一次城市下水道.

The farmers here sow once a year.

这里的农民一年播一次种子.

Once again there'stalk of very dark days ahead.

又有传言说以后的日子会非常艰难。

Once again he has broken his faith with them.

他又一次对他们不守信义.

Once again I warned her.

我又警告她一次.

All the sailors cheered once and again when they saw the Queen.

当水手看到女王时,欢呼声此起彼伏.

For even in Thessalonica you sent both once and again to my need.

16就是我在帖撒罗尼迦,你们也一次两次的,打发人供给我的需用.