to launch a surprise attack, sneak attack ☊ 
xuất kỳ bất ý ☊ (1) spoiled, rotten (2) (exclamation of surprise or to get sb’s attention) ☊
ôi ☊ spring a surprise attack ☊ đánh úp ☊ rise up unexpectedly, stage a surprise uprising ☊ đột khởi ☊