I felt chagrined at the wasted effort.

我为浪费了精力而感到懊恼。

youdao

Has missed preschool education this critical period often the wasted effort.

错过了学前教导这一要害期则往往事倍功半。

youdao

Proper methods, with high efficiency, and improper method: the wasted effort, efficiency is low.

方法得当，事半功倍，效率就高：方法不当，则事倍功半，效率就低。

youdao

Absent a common currency in the form of the dollar, the U.S. would still be a rich country, but far less vibrant for all the wasted effort necessary to facilitate interstate trade given 50 different floating money concepts.

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Hammering the irony home, the solution he proposed -- a "technology summit" of academics, tech companies, and content producers to develop a workable DRM system -- is exactly the sort of wasted effort Steve-O lambasted in his open letter.

ENGADGET: MPAA says it's committed to fair use, interoperability, and, uh, DRM

And woe be to he who actually develops for the platform, because he may soon find out that it all became wasted effort at the next over-caffeinated random user interface change.

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