Frequency - Word Form
  20 already
  20 beginning
  20 better
  20 certainly
  20 extinct
  20 form
  20 fridrikssen
  20 given
  20 height
  20 indeed
  20 lips
  20 neither
  20 others
  20 ourselves
  20 ready
  20 rejkiavik
  20 rose
  20 sky
  20 start
  20 stream
  20 suddenly
  20 suppose
  19 central
  19 coast
  19 danish
  19 dark
  19 dear
  19 difficulty
  19 eruption
  19 face
  19 horizon
  19 leave
  19 living
  19 lower
  19 reach
  19 rise
  19 room
  19 strange
  19 strength
  19 terrestrial
  19 thirty
  19 times
  19 true
  19 vertical
  19 white
  19 wide
  18 atmosphere
  18 bottom
  18 companions
  18 dense
  18 force
  18 fossil
  18 hardly
  18 heads
  18 icelander
  18 itself
  18 opened
  18 perfectly
  18 possible
  18 power
  18 provisions
  18 read
  18 sleep
  18 things
  18 tunnel
  18 understand
  18 understood
  18 whose
  17 across
  17 anything
  17 board
  17 book
  17 change
  17 clouds
  17 country
  17 expedition
  17 large
  17 lose
  17 means
  17 mine
  17 monsters
  17 near
  17 nephew
  17 o
  17 phenomenon
  17 remains
  17 running
  17 seems
  17 speed
  17 steps
  17 subterranean
  17 torrent
  17 twenty
  17 volcanic
  17 wonderful
  16 according
  16 added
  16 ah
  16 always
  16 beneath
  16 chance
  16 dinner
  16 direction
  16 explain
  16 got
  16 heavy
  16 help
  16 intense
  16 key
  16 land
  16 latin
  16 length
  16 less
  16 men
  16 met
  16 moved
  16 narrow
  16 order
  16 perfect
  16 places
  16 plants
  16 ran
  16 seen
  16 sentence
  16 short
  16 something
  16 sometimes
  16 space
  16 themselves
  16 to-morrow
  16 use
  16 violent
  16 years
  15 animals
  15 august
  15 because
  15 case
  15 clear
  15 clock
  15 excitement
  15 fresh
  15 greater
  15 heart
  15 horses
  15 instruments
  15 level
  15 mistaken
  15 mountains
  15 none
  15 paper
  15 passing
  15 pleasure
  15 quarter
  15 really
  15 regions
  15 remarkable
  15 rest
  15 shook
  15 stone
  15 stones
  15 study
  15 truth
  15 won