"valiant acts" is correct and usable in written English.
You can use it to describe actions carried out with courage and strength. For example, "In the face of adversity, the firefighter performed several valiant acts to help the community."
The climactic scene in this week's superlative dispatch from Downton Abbey has Lady Mary and Charles Blake stepping out after dinner to admire the new pig herd, only to find themselves caught up in what is surely one of the more valiant acts of animal husbandry of its day – and definitely the only one performed in formal dining attire.
I'm ready for more songs about valiant acts, stolen horses, and fatal car wrecks.
Roosevelt gave a short speech praising Sheridan's valiant acts while Porter's speech was an in depth review of Sheridan's life, including his days at West Point and his campaigns during the Civil War and American Indian Wars.
During the centennial of the Civil War starting in 1960, Georgia celebrated the Confederacy and the view that the state had seceded in a valiant act of defending states' rights against Northern aggressors.
Now Medea lives for the moral superiority that comes from having sacrificed everything for her love, never understanding that the reason she committed such valiant and heinous acts was in order to turn Jason into the kind of strong man she had always dreamed of possessing, and whose importance would be reflected onto her.
It seems unlikely, despite Ashley's valiant attempts to act as a cheerleader for neglected Strand stories such as "Sir Nigel" as "Doyle's masterpiece".
Despite a valiant late rescue act by Graeme Swann and the captain, Stuart Broad, they ended with their third-lowest total in 46 T20 internationals.
"This Is Not a Film," as they called their "effort" (that's the word used in the credits), is actually a playful pass at filmmaking; it is also a valiant and dangerous act of protest against the sinister farce of Panahi's punishment.
Music paid his way through a fine arts degree and made him the longest standing member of veteran blues rock act, Valiant Swart.
And that, in my opinion, was an act of quite valiant revolution for which the Women's Movement would have done well to canonise her.
During a fourth-quarter run by the Heat, James stunningly spiked a Hibbert layup off the backboard, but such stands, valiant though they may be, are acts of desperation, not the basis of a solid defense.
