缺点

Due to the numerical aperture of DVD pickup is large, and the characteristic size is small, the error of scalar diffraction theory is very large. The in-depth research work on vector diffraction of optical disc was carried out. The optical disk model was analyzed use the rigorous coupled wave theory, and some significative conclusion was obtained. These conclusions can use for guidance of scheme designing of optical pickup.

针对DVD读取头光学系统数值孔径大，光盘特征尺寸小，标量衍射理论误差大等缺点，采用矢量衍射理论对光盘的衍射进行了深入的研究，首次在光学读取头领域中将耦合波理论应用到光盘的衍射分析中，得到了一些有意义的结果，这些结果可以用来指导光学读取头方案的设计。

However, the extent of its products make digital, resolution is not high, relatively low power densities, poor reliability shortcomings.

但其产品存在数控程度达不到要求、分辨率不高、功率密度比较低、可靠性较差的缺点。

The major disadvantage is that not all goods can be digitized.

主要缺点是，并非所有的货物可以数位化。

Populus has several advantages as a model system. But because of the shortcomes that the chromosome of Populus are small, dioecism, without perianth, trunk of the tree is tall, the period of infancy is 6～7 years.

杨属植物作为林业研究的模式植物，具有优良的实验特性，但是由于杨属植物的染色体小、雌雄异株、无花被、植株高大、幼年期长达6～7年等缺点，给实验研究带来许多不便。

Diplodocus has many spots,from head to fail he sure has lot!

第七页：梁龙属爬行动物有许多缺点，但是他的运气比较好！

Traditionally, the numerical simulation studies of gas-solid turbulence flow are based on Reynolds-Averaged models which are not able to get accurate results. While with the rapid development of computer science, direct numerical simulation method becomes more and more vital hotpoint.

传统的研究气固两相湍流数值模拟是基于平均的思想，其无法描述流动的精确结构等缺点让直接数值模拟的方法在这个方面随着高性能计算机的出现而飞速发展。

I knew it was a disadvantage, But I don't know how to slow.

我知道他是个缺点，但是我不知道怎么变慢。

The only disadvantage here is that it's not free.

唯一的缺点是它的不自由。

My advantage is that I am handsome, but my disadvantage is that the is not so obvious .

我的优点是：我很帅；但是我的缺点是：我帅的不明显。

He has disadvantage , but after all, he is a good man.

他是有缺点，但总而言之，他是个好人。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。