\\\"unanticipated and disconcerting lines of development\\\"
\\\"unforeseen circumstances\\\"
\\\"a virtue unlooked-for in people so full of energy\\\"
\\\"like a bolt out of the blue\\\"
Adverb:
in a way that was not expected;
\\\"her brother showed up at the wedding out of the blue\\\"
造句
用作副詞(adv.)
His resignation came right out of the blue. 他的辭職來得很突然。
Out of the blue, he opened up a business. 出人意料他竟做起了生意。