long, short
Try to keep your sentences short.

complete, whole
broken, incomplete
full
She was a gifted child and could speak in full sentences at a very young age.

single
The argument can be distilled into a single sentence.

grammatical, ungrammatical
coherent
affirmative, declarative, negative
complex, simple
run-on (AmE)
opening
the opening sentence of the novel
‘Once upon a time … ’—the opening sentence to some of our very best-loved fairy tales

following
I came across the following sentence in a paper recently …

begin
finish
Peter finished Jane's sentence for her.

complete
Complete the following sentence: ‘I love dictionaries because … ’.

end
He tells her not to end her sentences with prepositions.

speak, utter
Troy uttered one last sentence.
The last sentence was spoken considerably more softly than the others.

construct, form, formulate, string together, write
He can barely form a grammatical sentence.
Cooke was so nervous he could barely string a sentence together.

parse
punctuate (usually figurative)
She punctuated her sentence with a well-aimed kick at his right shin.

read
I kept reading the same sentence over and over again.

contain sth, have sth
Does the sentence contain an adverb?

structure

maximum, minimum
the mandatory minimum sentence (AmE)

average
long, short
harsh, heavy, severe, stiff
lenient, light
reduced
He turned state's evidence in return for a reduced sentence.

indeterminate (esp. BrE)
appropriate
mandatory
The judge imposed the mandatory sentence for murder.

suspended
jail, prison
criminal
He suggested doubling the criminal sentences for company executives.

custodial, non-custodial (both BrE)
death
life

hand down, impose, pass, pronounce
The judge will pass sentence on the accused this afternoon.

be given, get, receive
begin (esp. BrE)
He has begun a life sentence for Carol's murder.

serve
He will have to serve a life sentence.

carry out, complete
ex-felons who have completed their sentences

await (esp. BrE)
He spent a week in custody awaiting sentence.

face
She could face a long prison sentence.

suspend
appeal (esp. AmE), appeal against (BrE)
review
commute, reduce
The death sentence may be commuted to life imprisonment.

overturn, quash (BrE)
uphold
The US Supreme Court recently upheld both of these sentences.

carry
This type of assault carries a maximum sentence of six months in prison.

sentence for
an eight-year sentence for burglary

under sentence of death
He was imprisoned under sentence of death.
He has been in prison for two months under sentence of death.