1. ContentIn grade 6 textbook, the content of pictures is so various. It covers a large of things so as to enhance the quality of teaching and learning. First, the book contains many pictures of real subjects. Thus, students can acquire the meaning of the vocabulary easily.

Besides, the content of pictures is related to the topic of the lessons. Those are images of indoor and outdoor activities, sports of Vietnam or around the world. Students also have opportunity to see some special architecture in the world.

The picture also brings many vivid images of secondary school students in different countries. In addition, the typical cultures of Vietnam and the world are presented through pictures. Moreover, traditional festivals and famous places are included in the photos as well. With the variety of pictures, most of new words are illustrated through photos. So, the content of pictures is utilized with high efficiency.

However, visual aid is little employed in grade 10 textbook. It seems that grade 10 students learn many more abstract words than concrete words. So, the use of photos is somewhat limited. Nevertheless, visual aids are still used to deliver the information of the lesson. The majority of the pictures in grade 10 textbook are quite profound. Many messages of moral perspectives and humanitarian activities are presented.

2. FunctionPhotos play a significant role to illustrate the words. Similarly, the use of preposition is also introduced through illustration images. Furthermore, pictures can draw students attention to the lessons. Therefore, the acquisition of students is enhanced. In this book, photos appeal students to reading, listening activities. Pictures are used to set the scene of a conversation. Depending on the pictures, students can be asked to anticipate the content of the dialog at the beginning of the task. This is the efficient technique for teacher to activate students learning.

Additionally, pictures are utilized to help students revise vocabulary. In order to help students practice speaking, pictures are designed to give them information to speak. Moreover, pictures are employed to engage students to do exercises and to support them in writing exercises.

Besides the functions for teaching and learning, pictures also send many messages of environmental protection, the preservation of national character, the spirit of unity, sexual equality and the welcome of international cultures. Some pictures are designed to develop students scientific passion and encourage them to participate in sport or outdoor activities.

Moreover, many pictures of beautiful places in the world are used to arouse the interest in learning about the world. So, they can be aware the importance of English.

In grade 10 textbook, there are only several pictures used to illustrate the meaning of the words. Most of the pictures are to indicate the main contents of each unit. Because the exercises for grade 10 students are different from the one for grade 6 students, the amount of pictures employed to help students do exercises are also restricted. Besides the functions have mentioned above, pictures are mainly utilized to elicit the ideas for speaking activities of every lesson.

Though the pictures of grade 10 textbooks have less function for teaching and learning than grade 6 textbooks, the authors present many passages about environment, moral education, culture and other positive realizations.

3. TypeThe book designer utilized a variety of pictures so as to maximize its efficiency. The images of real subjects are considered the best illustration for learning vocabulary. All of pictures are colorful. The harmonious combination of pictures, drawings makes the book more interactive. There are many kinds of pictures in order to cover the content of the lessons as subjects, furniture, sports, food, school things and places. Whereas pictures are the efficient tool to demonstrate things, drawings are used with the artistic advantages. Artistic drawings not only engage students to the content of the lessons, but develop their creativity and concentration which are seen as basic factors to success in learning. Finally, the book designer applied many types of pictures to support the teaching and learning process.

In grade 10 textbook, real pictures are used more than drawings. Almost the pictures and drawings are colorful. There are many images compiled from latest events of the most popular television broadcasts. This is a great connection between the book and the outside society. This helps to appeal the students to the content of the lesson before starting to study. For grade 10 students, the book designers do not employ plenty of cartoon drawings; they use more touching pictures about real life instead. Besides, the portraits of celebrities in Viet Nam as well as in the world are utilized to introduce the character of the reading texts.

Suggestion: besides concrete pictures, abstract pictures should be considered to use for the lessons related to entertainment topics. AttractionThe visual elements of the book are designed for great attraction. The contents of the visual element are clear. They explicitly reflect on the information of the pictures. Besides, the size of the pictures is chosen closely so that students can see information whether it is big or small. Both pictures and drawings are appropriately presented to avoid the boring repetition. Specially, with the drawings, funny and humorous elements were added to arouse students in order that they feel less stressed when they study. Moreover, students are also attracted by the creativity of the drawings. On the other hand, there are some implicit pictures or drawings in order to make them curious. This purpose is to promote students learning. In grade 10 textbook, the visual aids appeal students with clear and colorful pictures. However, the pictures in this book lack humor. The majority of the pictures just present obviously the content of the lessons. On the other hand, the attraction of visual aids is also affected by the quality of the pictures. Though almost the images are obvious, there are some pictures with poor quality. Students might have some difficulty seeing those unclear images. In contrast, most of the drawings are so attractive with funny and humorous characters. However, it could be more appealing if the characters are close to the age of grade 10 students. Suggestion: though colorful pictures are so attractive and clear, black and white images should be employed a little bit so as to maximize the attraction of these books.GroupVisual elements focus on the age of grade 6 students. Because pictures are close to users, this enhances the interactiveness between the book and students. Pictures do not centre on any particular group. An nearly equal number of male and female images are presented. The remarkable point of visual elements is that it still has pictures of ethnic minority students. These pictures somewhat show the concern of the society to ethnic minority students. This shows that this course book is designed for everyone in this country, not only for those in the city or only for the majority of the population; in other words, the book composers have taken the issue of moral issue into account. On the other hand, based on those pictures, teachers can help students who come from plan regions? realize their advantages. In grade 10 textbook, most of the characters in the book are not close to the age for grade 10 students. This may affect the interactiveness between the book and students. In addition, a considerable number of characters in the series 2 of grade 10 textbook are foreigners. Because this book is designed for Vietnamese students, the images of them should be Vietnamese together with other peoples. Furthermore, the figures of drawings are so young? to grade 10 students. They seem to be more suitable for primary students. Suggestion: for grade 10 textbook, pictures from real activities of grade 10 students should be employed in order to increase the interactiveness between the material and learners.ValueThe visual elements have a great value for learners and teachers. With a good range of illustrations, the visual elements facilitate the students learning. Besides it can increase the comprehension of the lessons, it encourages students to try their best. When pictures can play a role as motivator, it contributes a considerable value to teaching and learning process. Moreover, the visual elements also give students chances to have exposure to new knowledge of society. Because this book is designed for grade 6 students, the authors also consider helping students discover their potential hobbies about entertainment and science. Furthermore, with the great support of visual elements, teachers can increase the success of their lectures. They also save much time to find pictures to demonstrate the content of the lesson because it is available in the book. In grade 10 textbook, although the illustration photos are quite limited, the visual images still play a significant role in the success of learning and teaching purposes. The photos related to topics help learners memorize the main contents of the lessons better and longer. In addition, based on the attractive images, students are able to generate more ideas about the topics in the speaking tasks. Besides learning and teaching value, students are received a great inspiration from the pictures of the book. This is a spiritual benefit which motivates students by helping them realize the true value of life. When students understand the implication in these pictures, they will be more responsible for their duties. As a result, students will put extra effort in their study. CONCLUSIONAfter investigating the 2 sets of textbooks, we have a clearer idea on the effectiveness of visual aids. Students will be supported to develop the four skills through images considerably. Moreover, photos also play an essential role in teaching and learning purposes when they help learners memorize the lessons. Photos are employed to engage students to participate in the lesson activities. Specially, visual images are not also impact on learning process, but influence the perspectives of students about life and society. Therefore, when selecting the photos for books, the author should consider both learning purposes and the appropriateness of the visual images in the educational setting.