1. Which of the following plane figures have reflectional symmetry?

2. Three comprehensive parameters that is reflectional degree X1, brightness rate X2 and diffuse light X3, are put forward in optical space domain of lustre sensation physics.

3. Critical thinking is a special reflectional recognition. The scientific feature of investigation decides its important function in the whole investigation.

4. Reflectional visible light sensor that can magnify the intensity of reflectional light by Darlington transistor is adopted in the sensor module.

5. This character, together with the secular modernity, enlightening modernity, reflectional modernity and aesthetic modernity, constitute the multiple aspects of modernity.

6. This paper focuses on the principal problems in symmetry detection such as the selection of the symmetric points in image and the location of reflectional symmetry axes and deeply research in them.

7. Three parameters in stimulation space domain of lustre sensation physiology that is physiological reflectional value Y1, physiological lustre value Y2 , physiological diffuse light value Y3.