with a lever stationary part 62 which is received in one of the engaging slide grooves 11 between another two of the engaging slide grooves 11 attached with the lock pins 3 the lever 62 at the lower end thereof is a fixing end 621 which passes through the bottom end piece 14 and is fastened with a nut 622 to form a stationary part the cylindrical pipe 61 at the upper and the lower ends thereof has a pivot 611 joined to the spacing board 7 such that it is possible that the spacing board 7 can be lifted or descended with cylindrical pipe 61 along the engaging slide groove 11 the spacing board 7 is disposed and taken in a frame enclosed by two upright posts in practice the spacing board 7 can be a writing board such as an electronic whiteboard a display panel or an illumination panel so that characters or pictures can be shown on the board or an effect of illumination can be performed besides the spacing board 7 can be applied to a counter in a bank or a commercialized counter or used for a dressing table in a beauty salon as a lifted mirror in order to protect the upper and the lower sides of the spacing board 7 a t shaped edge sealing plate 71 can be used as a side cover respectively the upper side thereof is provided with a lock 72 and the lock 72 extends laterally a key plug 721 to engage with a preset engaging hole 31 in the respective engaging pin 3 such that the spacing board 7 can be fastened firmly.