答案：B分析：考察点为动词不定式做目的状语。A中added为过去分词，

答案：B分析：考察点为动词不定式做目的状语。A中added为过去分词，一般作后置定语，此处语意不通。C中有are，这样整个句子就多了一个谓语，而is是整个句子的谓语，因此排除。D，整个句子的主语是the gray scale，为单数， 应该是and adds 才正确。参考译文： 灰度比例尺，一从黑到白渐变的色调系列，在计算机图形中被用来增加图像的细节。

Kết quả (Anh) 1:

Answer: b analysis: study for verb infinitives to cover its financial problems. Added in a past participle usually postpositive, here meaning doesn't make sense. Are in c, so that the entire sentence on more than one predicate, is the predicate of the sentence as a whole, and therefore excluded. D, the subject of the sentence as a whole is the gray scale, for the singular, should is and adds just the right. Text: gray scale, from black to white gradient color series in computer graphics were used to increase the detail of the image.

Kết quả (Anh) 2:

Answer: B analysis: study points infinitive do adverbial purpose. A is added as a past participle, generally for post-modifier, where semantic barrier. C there are, so that the entire sentence on more than a predicate, and the predicate is the whole sentence, and therefore excluded. D, the whole subject of the sentence is the gray scale, singular, and adds it should be correct. Passage: gray scale, a hue range from black to white gradient, in computer graphics are used to increase the detail of the image.

Kết quả (Anh) 3:

The answer: B analysis: the study point is the verb is not set to do. A added for the past participle, general pictures, the semantic barrier. In C, there are are, so that the whole sentence is more than a predicate, and is is the whole sentence of the predicate, so the exclusion. D, the subject of the whole sentence is gray scale the, for the singular, it should be adds and is correct. The gray scale, a series of tones from black to white, is used to increase the details of the image in the computer graphics.