holographic projection(全息投影) bear generator(小熊发电机) power station(发电站) automatic drawing machine(自动绘图机) carousel(旋转木马) magnetic small aircraft(磁力小飞机) sundial(日晷) solar fan(太阳能风扇) hydraulic excavator(液压挖掘机) hook roller(胡克滚筒) elevator lift(电梯升降机) catapult(投石车) space instrument(太空仪) making clocks(制作钟表) lever balance(杠杆天平) portable power generator(手摇发电机) peristaltic robot(蠕动机器人) traffic lights(红绿灯) automatic serve machine(自动发球机) making electric fan(制作电风扇) conductor detector(导体检测仪) piano music box(钢琴八音盒) solar energy driven car(太阳能小车) double propeller aircraft(双螺旋浆飞机) solar helicopter(太阳能直升飞机) newton's cradle(牛顿摆) ferris wheel(摩天轮) balance bird(平衡鸟) make table lamp(制作小台灯) vacuum cleaner(吸尘器) balance robot(平衡机器人) money detector(验钞机) wind power generation(风力发电) air floating ball(空气悬浮球) lifting crane(起重吊机) hydraulic elevator platform(液压升降台) voice control car(声控小车) shooting machine(投篮器) paddle steamer(明轮船) earthquake alarm(地震报警器) periscope(潜望镜) hydraulic mechanical arm(液压机械手臂) mechanical dog(机械狗) electric gliding aircraft(电动滑翔飞机)

educational selection experiment(益智精选实验)