adj.不谙世故的;不复杂的
He was confiding, good-natured, unsophisticated, companionable. 他为人坦率,一团和气,世故不深,蔼然可亲。
So unsophisticated was his mother in these matters that she believed him. 他母亲对这类事完全外行,也就相信了他的话。