Manual testing can be completely effective for testing new or modified functionality, but manual testing is almost always impractical as a means of guarding against regression.

手工测试对于新的或是修改的功能而言非常高效，但对于防止回归而言又总是不切实际。

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Thus, common document retention policies fore-mail and electronic documents are not completely effective or reliable.

因而普通的文件保留政策，对电子邮件和电子文件来说，并不是完全有效或者可靠的。

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When the process is done for real on a large scale, the treated water will first get pumped into a reservoir for further refinement, because of health department concerns that the process may not be completely effective.

CNN: San Diego hopes to recycle waste water

While Dash has done a good job of keeping the overall system responsive, it can't completely hide the effective difference between broadband and early dial-up modems.

ENGADGET: Switched On: Dash delivers open roads, open questions (Part 1)

The Iraqi security forces should do the brunt of this because they actually will be more effective once completely trained.

NPR: Is Victory in Iraq Still Possible?