bad, big, deep, desperate (esp. BrE), dire, huge (esp. AmE), major, real, serious, terrible
We're in deep trouble now!

endless
potential
current, recent
ongoing
domestic, family, marital
financial, money
She got into serious financial trouble after running up large debts.

legal, political
back, hamstring (sports), heart, etc.
boyfriend, girl, man, etc.
He was obviously upset, and muttered something about girlfriend trouble.

car, engine
foul (AmE) (in basketball)
Most of the game we were in foul trouble.

mean, spell
She knew that a hygiene inspection could spell trouble for her restaurant.

have, suffer from
He has had back trouble since changing jobs.

get (yourself) into, run into
The company soon ran into financial trouble.

keep out of, stay out of
cause, lead to
The printer's causing trouble again.

avoid
forget, leave behind, put behind you
They are hoping to leave their recent troubles behind.
He put his past troubles behind him and built up a successful new career.

come
Trouble often comes when you're least expecting it.

begin, start
Her troubles began last year when she lost her job.

in trouble
When she saw the teacher coming she knew she was in big trouble.

trouble for
He got into trouble for not doing his homework.

trouble with
I've had endless trouble with my car.
He is in trouble with the law again.

a cause of trouble, a source of trouble
a history of … trouble
She has a history of back trouble.

have trouble doing sth
I've had trouble sleeping recently.
He was having trouble breathing.

in times of trouble
In times of trouble she always turns to her mother.

teething troubles (figurative, esp. BrE)
After some teething troubles, the system is now up and running.

trouble ahead
I can see trouble ahead.

crowd (esp. BrE)

cause, make
He had a reputation for making trouble in the classroom.

start
Just don't start any trouble.

be asking for, be looking for, court, stir up
He was asking for trouble when he insulted their country.
Fans wandered the town after the match looking for trouble.

want
Look, we don't want any trouble, so we'll leave.

be brewing
There was trouble brewing among the workforce.

begin, blow up (BrE), flare (BrE), start
Trouble blew up when the gang was refused entry to a nightclub.
We left before the trouble started.

spot
Extra journalists have been sent to the main trouble spots.

trouble between
trouble between the races

considerable, enormous (esp. BrE), great
They went to enormous trouble to make her stay a pleasant one.

bring (sb), cause (sb), give sb, make, put sb to
I don't want to make trouble for her.
I don't want to put you to any trouble.

go to, take
We took the trouble to plan our route in advance.

be worth
Do you think it's worth the trouble of booking seats in advance?

save sb
Why don't we bring a pizza to save you the trouble of cooking?

thank sb for
Thank you very much for all your trouble.

be more trouble than it's worth
Growing your own vegetables is more trouble than it's worth.