elevated, high, significant, substantial
record
Industrial output has reached record levels.

increasing, rising
excessive
Excessive levels of lead were found in the water.

low
decreased, reduced
decreasing, falling
moderate
varying
They work hard, but with varying levels of success.

detectable, undetectable
generous (esp. BrE)
a generous level of financial support for the arts

permitted, recommended, required
permitted levels of chemical pollutants

acceptable, adequate, necessary, safe
an acceptable level of risk

normal
Her blood pressure has returned to its normal level.

realistic, reasonable
dangerous, unacceptable
worst
the worst level of business failure since 1997

unprecedented
maximum, minimum
desired, optimal
baseline
noise, ozone, pollution, radiation
crime, poverty
funding, staffing
blood-sugar, cholesterol, hormone, etc.
confidence, energy, stress

achieve, attain, reach
They have achieved higher levels of efficiency.
Crime has reached its highest level ever.

remain at
She predicts that fuel prices will remain at current levels.

boost, elevate, improve, increase, raise
maintain
bring down, decrease, keep down, lower, reduce
control, regulate
adjust, alter, change
set
Emissions are well below the levels set by the WHO.

exceed
There will be stiff penalties if companies exceed these levels of pollution.

assess, determine, measure, record
check, monitor

go up, rise, soar
decrease, drop, fall, go down, plummet
change, differ, vary
exceed sth

above a/the level
Mortgage rates were 10% above their current level.

at a/the level
Rents will be kept at this level for another year.

below a/the level
Radiation is well below the permitted level.

level of
They were asked to indicate the level of distress they experienced as a result of their experiences.

basic, elementary, low
The teaching is at quite a basic level.

entry
They have a good range of entry-level computers for beginners.

intermediate
advanced, high
Her illness has reached an advanced level.

degree
3rd-grade, 11th-grade, etc. (AmE)
grade (AmE)
He's reading at grade level (= at the average level for his grade).

difficulty
The difficulty level of the exercises in the book varies widely.

fitness
a sport suitable for people of all fitness levels

educational

attain, reach
students who have reached the intermediate level

complete, do, take
You need to do all three levels to qualify as a chef.

above a/the level
His English is way above the level of the other students.

at a/the level
students at intermediate level
She has played tennis at a high level.

below a/the level
The book is not suitable for students below degree level.

level of
language students at different levels of proficiency

sb's comfort level (= the level at which someone feels safe and comfortable)
take sb/sth to the next level
It's time to take my career to the next level.

high, upper
the upper levels of the civil service

low
senior
global, international, local, national, regional
grass-roots
The party needs to win support at grass-roots level.

board
These decisions are made at board level.

federal, ministerial (BrE)

reach, rise to
He rose to the level of general manager.

at a/the level
At the local level there's a lot to be said for the plan.

on a/the level
The thing has to be organized on an international level.

conscious, subconscious, unconscious
At a conscious level, I was satisfied with my life.

deep
superficial
detailed
We probably need to look at this problem at a more detailed level.

general
practical
theoretical
political
tactical
macro, micro

at a/the level, on a/the level
On a superficial level everything appears to be in order, but at a deeper level you an see that there's a lot wrong.

high, low
ground, sea, water
the problem of rising sea levels

eye, knee
a shelf at eye level

adjust, change, lower, raise
They are going to raise the level of the banks to prevent flooding.

above a/the level
200 m above sea level

at a/the level
The plane was flying at a very low level.

below a/the level
below the level of the clouds

on a level with
On the second floor you are on a level with the treetops.

to a/the level
The water rose to the level of the ground floor windows.

a change in level, a change of level

ground, lower
higher, top, upper

on a/the level
Are we on the right level for the restaurant?

to a/the level
Take the elevator to Level Four.

be, look, seem
get sth, keep sth
Make sure you get the shelf level before screwing it in.
Keep the pot level, or you'll spill the coffee.

absolutely, completely
The floor has to be absolutely level.

approximately, more or less, nearly

be
come, draw
As they reached the final bend, Graham drew level and threatened too overtake him.

almost, nearly

with
The top of the water came level with her chin.