There are structural obstacles that make these things harder to do.

有一些结构上的障碍使得这些事情更加难实现。

youdao

By then, much to my delight, Luther and Eliot were raring to go-to climb, explore and inadvertently test the structural soundness of things the way only kids can do.

这时，我高兴地看到路德和艾略特急切地要去攀登，去探索，以只有孩子才会采用的方式，在无意中检验物体结构的安全性。

youdao

Grown this way, smooth muscle secretes collagen, a structural protein that is, among several other things in the body, an important component of the walls of blood vessels.

采取这种方式生长，平滑肌可分泌胶原，一种结构蛋白，是人体中除其它几种物质外组成血管壁的重要成分。

youdao

That RNA is made into proteins, and proteins are the working molecules of the cell, they're enzymes, they're structural molecules, they're are proteins that exist in the membrane that allow things to go in and out of the cell, so really the working molecules are the cell in every sense.

这些RNA指导合成蛋白质,蛋白质是细胞生命活动的承担者,它们可以是酶,或是结构性分子,也可以存在于细胞膜上的膜蛋白,能够让一些物质通过它们进出于细胞,所以蛋白质才是真正意义上,细胞生命活动的承担者

耶鲁公开课 - 生物医学工程探索课程节选

There are a variety of reasons as to this and some of them are benign, such as raised costs now because more people want new procedures, but administrative costs, paperwork, perverse incentives, all kinds of structural things are wrong with the system that have to be fixed.

FORBES: Magazine Article

As I wrote in my earlier blog, the IFS and pretty much every other economic forecaster expected the OBR to raise its estimate of the structural current deficit, given what we knew about the way they forecast these things.

BBC: The Bank, the OBR and Mr Osborne

But what we also have to understand is that if I take all the steps that I've put forward and Congress follows my lead on the non-defense discretionary spending, we're prudent in terms of defense spending, and we do all the things that we've talked about, we've still got this structural deficit that we've inherited.

WHITEHOUSE: President Obama Takes Questions from Senate Democrats