dig deep

基本解释

To plant the tree, we must dig a three-foot-deep hole.
种植树，我们必须开掘一个三脚深孔。
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They dig deep, stand-up foxholes, which are safe except under direct artillery fire (and which are better than U.S. slit trenches).
他们挖很深的，能容人站立的散兵坑，这些散兵坑很安全，除非暴露在直接炮火之下（比美军的狭长散兵壕更好）。
In order to dig out accurate and deep-seated information, modern technology is applied to the medical images.
将医学图像融合先进的技术，能够获得更加可靠详实的信息。

Those names and symbols dig down deep-deep-deep into our political mindsets.
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Then you shift gears and blame the teachers unions for protecting bad teachers that ought to be fired and dig into the all-too-deep trough of anecdotal evidence to dredge up a few examples of really bad teachers that were hard to fire.
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Subscribers not interested in upgrading yet can find similar functionality tied to Spotify's library with the EchoFi tool, but this venture represents the service's debut of an "all-new intelligent recommendation engine" meant to dig the tracks you want out of its millions-deep library.
ENGADGET: Spotify Radio feature turns into an app, offers Pandora-like stations with unlimited skips