Chinese puzzle
argument
baffling problem
brain twister
conundrum
crossword puzzle
crux
enigma
enigmatic question
excuse
explanation
floorer
for which
for why
from what cause
ground
how come
jigsaw puzzle
knot
knotty point
mind-boggler
mystery
mystification
nut to crack
on what account
perplexed question
perplexity
poser
pourquoi
pretense
pretext
problem
proof
puzzle
puzzlement
puzzler
question
question mark
rational ground
rationale
reason
reason for
reason why
riddle
sixty-four dollar question
stated cause
sticker
stumper
the big idea
what
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beads
beer
birds
both
chesterfield
classes
color
cordon
corn
dare
fighting
group
late
latter
leaves
ought
rhymster
rocks
servants
ship
shrubs
stairs
straw
tea
thine
trees
wheel
would
wouldest
yet
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Ally
Bi
Bligh
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Pty
Shanghai
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Thai
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Versailles
Vi
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Zhuhai
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