1. gullible
Tom discovered just how gullible Mary was.
Dana is so gullible, she would believe anything
I'm a bit gullible - I often believe the crazy stories my friends tell me.
I'm amazing gullible, everyone's able to lie me.
He took all of her money. She is so gullible.
There are any number of miracle cures on the market for people gullible enough to buy them.
a gullible person is easy to trick because they trust and believe people too easily
It's amazing how gullible people are, he said to himself.
The island was bought from gullible inhabitants of Mannahata.
a gullible person is easily persuaded to believe something
These overpriced souvenirs are sold to gullible tourists.
They take advantage of gullible tourists.
Surely you weren't gullible enough to believe all that?
You are very gullible
The word "gullible" is not in the dictionary.
2. naive
It's naive of you to believe that.
Don't be so naive!
You must be very naive to be taken in by such a story.
The naive man blushed with shame.
In most cases, people, even the most vicious, are much more naive and simple-minded than we assume them to be. And this is true of ourselves too.
Are you still letting last night's fight bother you? That's so naive.
Am I that selfish or he's just too naive?
Stop slagging off my brilliant idea, it's not naive at all!
When she first saw the size of it, my naive girlfriend was blown away.
The townspeople were astonishingly naive about what the smugglers were.
They were too naive to understand the necessity of studying.
a naive person lacks experience of life and tends to believe things too easily
Innocence personified, being naive in such a world can be quite a burden.
Andy had a sweet, naive look when he smiled
/naɪˈiːv/ She was very naive to believe that he'd stay with her.