The phrase "a slightly surprised" is correct and usable in written English.
It can be used to describe someone who is experiencing a mild level of surprise in a particular situation.
Example: "She had a slightly surprised expression when she heard the unexpected news."
Alternatives: "a bit surprised" or "somewhat surprised".
Ilasaca gave me a look, slightly surprised, unimpressed.
4.33am GMT Wicket!! Yuvraj c Morgan b Finn 0 Caught at point off a rotten, slightly surprised looking fend away that looks as if it came off the back of the bat as if he didn't expect or fancy Finn's pace at all.
As a grinning, charmed and (slightly) surprised Mr. Hunt looked on, a roster of political A-listers offered video tributes to their friend — everyone from President Obama ("I hope you get 40 more") and ABC's George Stephanopoulos and Caroline Kennedy ("One of the best gifts I got from Uncle Teddy was you").
He suggests he keep them in the top of a cupboard, which, one is slightly surprised to hear, closes the matter: "This little piece of symbolic hospitality was enough to bring her peace of mind".
So when the singer was photographed this weekend by x17online.com in a pirate costume worthy of a Disney blockbuster, we were only slightly surprised.
But Koç is a remarkable institution, with an ice rink, a celebrity Pilates coach, and a writer-in-residence, so I was only slightly surprised to learn there was also an African dance class with live drummers.
"Melk is a nice town," he says, and is slightly surprised I've never been there myself.
In response to a reporter's question, he said, as if slightly surprised: "Oh, I didn't ask for their vote".
As the bass thumped and the strings soared, Mr. Lekman sang of his first kiss: "Sometimes I almost regret it, like I regret my regrets/I see myself on my deathbed saying, 'I wish I'd loved a little less.'" All night he seemed slightly surprised that the crowd was so reverent.
