His death was totally unexpected.

他的死亡完全出乎意料。

He made a brief, unexpected appearance at the office.

他出乎意料地在办公室露了一下脸。

Help may also come from some unexpected places.

帮助也可能来自某些意想不到的地方。

'Hello,' he said. 'This is an unexpected pleasure.'

“嗨，”他说。“这真是个意外之喜。”