英文關鍵字
and
brown
change
cliff
close
color
construction
cracked
day
dry
ecosystem
erosion
explore
flattened
focus
fragile
geologic
geological
geology
gray
graybrown
horizontal
landform
layers
material
mountain
natural
nature
outdoor
particles
patterns
people
rock
rocks
rough
shape
small
stone
surface
tall
texture
textures
thin
wall