"Once and only once" is the Extreme Programming phrase.
“一次且仅一次”是极限编程的座右铭。
It also makes sure dependencies are loaded once and only once.
它也确保依赖项已经加载一次,且仅加载一次。
Use QoS 2 when a message is to be delivered once and only once.
当消息仅传递一次时,使用QoS 2。
She says the only work needed once beets have been thinned is weeding and, when the weather is dry, a weekly watering.
VOA: special.2010.03.02
Milton will only use the word career once in his poetic oeuvre and it comes -- it will come pretty soon, actually, in Sonnet Number Seven.
弥尔顿在他的全部诗歌作品中只用过一次事业这个词,我们马上就会看到,在十四行诗的第七行。
It's a comedy that you only get once you performed and once you know what's happening, and
这种喜剧只有你自己明白,只有你自己知道发生了什么,
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