Multifunctional Combinable Glasses Technical Field The present invention relates to the field of glasses and particular to multifunctional combinable glasses. Background As computers, televisions and smart phones are widely used, eyesight problems are becoming unusually severe. Currently, glasses are often necessary daily consumables to assist eyesight and they are widely used in various industries and groups. In the industry of glasses, in addition to common myopic glasses, there are astigmatic glasses, sun-glasses and light-sensitive glasses, etc. But these glasses cannot achieve a superposition effect. People wearing myopic glasses cannot simultaneously wear sunglasses or 3D movie glasses. For example, when myopic people participate in outdoor activities, they will be exposed to strong sunlight or reflected light of snow field, but they cannot simultaneously wear polarized sunglasses. When they drive back at night, they may encounter glaring car lights, but they cannot simultaneously wear driving sunglasses. It is therefore very difficult for myopic people to wear other types of glasses. Summary of the Invention The objective of the present invention is to provide multifunctional combinable glasses. According to one aspect of the present invention, it provides multifunctional combinable glasses comprising a first glasses body and at least one second glasses body matchable with the first glasses body. The first glasses body comprises temples, a first frame and first lenses. The second glasses body includes a second frame and second lenses. The temple or the first frame is provided with a first attracting member. The second frame is provided with a second attracting member. When the first and second attracting members are attracted to each other and thus connected, the first and second glasses bodies are matched together. The first and second lenses are of different types. 1 An advantageous effect of the present invention is that the second glasses body can be matched to the first glasses body through attraction and matching between the first and second attracting members so that a superposition effect of the first and second lenses is achieved. When people wearing myopic glasses participate in outdoor activities, they can wear the second glasses body equipped with polarized lenses, so that both their eyesight can be improved and their eyes can be protected from strong sunlight. In a similar way, myopic lenses can cooperate with other types of lenses to fit for other different environments. Brief Description of the Drawings Figure 1 is a schematic view of multifunctional combinable glasses according to an embodiment of the present invention; Figure 2 is a schematic view of multifunctional combinable glasses according to another embodiment of the present invention; and Figure 3 is a schematic view of multifunctional combinable glasses according to yet another embodiment of the present invention. Detailed Description of the Embodiments Hereinafter, the present invention will be further explained in conjunction with the accompanying drawings. As shown in Figure 1, the present invention provides multifunctional combinable glasses comprising a first glasses body 1 and at least one second glasses body 2 matchable with the first glasses body 1. The first glasses body 1 comprises temples 11, a first frame 12 and first lenses 13. The second glasses body 2 comprises a second frame 21 and second lenses 22. The first frame 12 is provided with a first attracting member 3 and the second frame 21 is provided with a second attracting member 4. When the first and second attracting member 3, 4 are attracted to each other and thus connected, the first and second glasses bodies 1, 2 are matched together. The first and 2 second lenses 13, 22 are of different types. Through attraction and matching between the first and second attracting members 3, 4, the second glasses body 2 can be matched to the first glasses body 1 such that a superposition effect of the first and second lenses is achieved. When people wearing myopic glasses participate in outdoor activities, they can choose the second glasses body 2 equipped with polarized lenses so that both their eyesight can be improved and their eyes can be protected from strong sunlight. In a similar way, myopic lenses may cooperate with other types of lenses to fit for other different environments. Usually, one of the first and second attracting members 3, 4 is a permanent magnet and the other one is an iron block or an iron alloy block. It is common that the first attracting member 3 is chosen as a permanent magnet and the second attracting member 4 is a non-magnetic iron block. Because the second glasses body 2 for a combined use with the first glasses body is usually placed in a user's pocket or bag, if the second attracting member 4 of the second glasses body 2 is of magnetic, it might have an impact on cell phones, watches, bank cards or the like that are usually placed in the pocket or bag. In more serious situation, the cell phones, watches, bank cards or the like cannot work normally due to the impact of strong magnetic forces. However, if the second attracting member 4 is chosen as a non-magnetic iron block or iron alloy block, the above problem can be eliminated. To ensure flatness and an aesthetic appearance, the first attracting member 3 is usually embedded in the interior of the first frame 12 and the second attracting member 4 is embedded in the interior of the second frame 21. After embedded, the embedding positions of the first and second attracting members 3, 4 are shown as a flat surface. By embedding the first and second attracting members 3, 4, protrusions of the same can be prevented. In this way, the contact surfaces of attraction are smoother which will not cause a hooking phenomenon. In the case that the first attracting member 3 is arranged on the first frame 12, when the second attracting member 4 on the second frame 21 is attracted and connected to the first 3 attracting member 3, the second frame 21 covers on the first frame 12. When the second frame 21 covers on the first frame 12, the first and second lenses 13, 22 can be better superimposed together to achieve a desired effect. At the same time, the second lens may be a yellow lens resistant to blue rays and having a night vision goggles function. Or it may be of other type of lens so as to effectively protect the user's eyes, eyesight and alleviate fatigue. As shown in Figure 3, in order to guarantee a stable attraction effect, the first and second attracting members 3, 4 are all provided in plurality numbers. A plurality of the first and second attracting members 3, 4 is matchably positioned in pairs. The first attracting members 3 can be scattered on the temple 11 or the first frame 12 and the second attracting members 4 are scattered on the second frame 21. By providing with a plurality of first attracting members 3 and a plurality of second attracting members 4, the attraction and connection between the first and second attracting members 3, 4 can be more stable. Shaking and disengagement can also be avoided. As shown in Figure 2, it provides another embodiment of the present invention. It differs from the embodiment as shown in Figure 1 in that the first attracting members 3 are placed on the temple 11 and the second frame 21 comprises extension portions 23 on both ends thereof. The extension portions 23 are corresponding to a stem portion of the temple 11 and the second attracting members 4 are arranged on the extension portions 23. By providing such extension portions 23, the second glasses body 2 can better cooperate with the first glasses body 1 which causes the attraction and connection more stable and secure. In this way, the technical effect of embodiment shown in Figure 1 can be achieved too. The above is only some embodiments of the present invention. Various modifications and improvements can be made by those skilled in the art without departing from the inventive concept of the present invention and within the protection scope of the present invention. 4