"improvised speech" is a correct and usable phrase in written English.
It can be used to refer to a speech that is made without prior planning or preparation. Example: The politician gave an impressive improvised speech in response to the unexpected question, leaving the audience in awe of his natural speaking abilities.
She was good enough to hold her own with any of her more famous contemporaries, and could rescue the worst of the then popular novelty songs by inspired spontaneity involving both instrument-like ingenuity and improvised speech.
The 82-year-old actor and director gave a bizarre, improvised speech at the Republican National Convention in Tampa, Fla., in August endorsing Romney.
His improvised speech so inspired the audience that the local paper reported it.
In an improvised speech considered to be one of the finest of his career, he promised a package of major devolutionary measures in a move credited with helping the Better Together campaign win the referendum.
The results appeared to catch even Mulcair himself off-guard, as he delivered a largely improvised speech accepting the results after they were delivered.
Trying to keep things light-hearted, I for some reason forced myself into a prolonged improvised speech about dating conventions and how we should try to explode them by getting her to pay for all of the drinks.
Language classes can be taught by immersing students in a role-playing scenario in which they are forced to improvise speech or writing in the language they are learning.
In a high school gymnasium here on Friday, a 20-minute drive from his birthplace, Mr. da Silva was in his element, crisscrossing a stage with a microphone and energizing 3,000 supporters with an improvised stump speech.
In his Thursday night address, broadcast on national television, an unusually reserved looking Chávez who read rather than improvised his speech, said Cuban doctors had detected "a strange formation in the pelvic region" following the first round of surgery.
At graduation in 1969, the entire class, many parents, and faculty members watched as Clinton rebuked a sitting Republican senator, Edward Brooke, of Massachusetts, during her now famous, largely improvised commencement speech.
On "September," Sam Shepard was granted permission to improvise a speech, and, according to Wiest, ended up talking about leaving Montana to go East to medical school.
