file:1-41_Why_Can__t_I_Have_Cake_for_Dinner-1.pdf file:1-40_Everybody,_Move_Your_Feet!-1.pdf file:1-39_A_Cavity_Is_a_Hole_in_Your_Tooth-1.pdf file:1-38_What_Makes_a_Shadow-1.pdf file:1-37_Sounds_All_Around-1第1辑第6本.pdf file:1-36_Snow_Is_Falling-1.pdf file:1-35_Pop!-1.pdf file:1-34_Is_There_Life_in_Outer_Space-1.pdf file:1-32The_Big_Dipper-1.pdf file:2-78 What Happens to Our Trash-1.pdf file:2-77 Terrible_Tyrannosaurs(1).pdf file:2-76_Where_Do_Polar_Bears_Live-1.pdf file:2-75_Where_Did_Dinosaurs_Come_From-1.pdf file:2-73 what_makes_a_megnet.pdf file:2-72_What_Is_the_World_Made_Of-1.pdf file:2-71_Switch_On,Switch_Off-1.pdf file:2-70_How_People_Learned_to_Fly-1.pdf file:2-69_Gravity_Is_a_Mystery-1.pdf file:2-68_Forces_Make_Things_Move-1.pdf