A dictionary of Confusable Phrases: More Than 10,000 Idioms and Collocations

jungle law • natural law
jungle law —(also: law of the jungle) the superiority of brute
force or self-interest in the ruthless struggle for survival: It
was awkward having to explain jungle law to someone who
had never emerged from a well-kept shrubbery.
natural law —(also: law of nature) 
1
. is used to refer to a par-
ticular phenomenon always occurring if certain conditions are
present : Gravity is a natural law (a law of nature) that is
dependable and constant. 2. is used of ideas, etc. as implanted
by nature in the human mind: In political theory, Spinoza
argued that human beings fundamentally act in accordance
with natural law.
just about • only just
just about—
1
. almost: He knows just about everything there
is to know about shipping cargo out of Miami. 2. (followed
by Infinitive) on the point of doing smth.: He was just about
to fold up the newspaper when he spotted the classifieds.
only just—
1
. a short time ago: I only just heard about the
inappropriate way Ms. Jacobson behaved. 2. barely; almost
not: The farmhouse can only just be seen from the road when
the trees are not in leaf.
just you wait • wait for it
just you wait—(also: you wait) is used to imply an angry
threat, promise, or warning: We’ll teach them a lesson I tell
you, just you wait and see.
wait for it—is used to create an interval of suspense before
saying smth. unexpected: We can have a shower and … wait
for it, dinner at the Palazzo Capucci.
K
keen of something • keen on something
keen of something —highly sensitive to smth.; sharp of sight,
smell, etc.: A black rhino has poor eyesight, but it is keen of
hearing and smell.
keen on something —very fond of smth.; enthusiastic about
smth.: I was lucky to have a girl like Betty who was keen on
football.