平均需要10周的时间才能完成一幢房子的销售。

It takes an average of ten weeks for a house sale to be completed.

《柯林斯英汉双解大词典》

我还得花很长时间才能完成。

It'll be a goodish while yet before I've finished.

《牛津词典》

你需要算一算要花多少时间才能完成分配的任务。

You'll need to calculate how much time the assignment will take.

《牛津词典》

Here is the pitch in--of--a string an octave higher so you can see it this way. As you probably know, if you take a long string and pluck it, it's going to take that long string a long time to pass that sort of cycle, if you will, just one pass through that cycle.

这也是个音高,一个高八度的音弦,你可以这样这样看 你们可能知道,如果你拨动长弦,长弦要经过很长时间,才能完成一个震动周期,如果你想,可以尝试下

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