---What were you doing when the UFO ?-I a milk shake.A. reached madeB. reached was m

问题补充：

---What were you doing when the UFO ?

---I a milk shake.

A. reached, made

B. reached, was making

C. arrived, made

D. arrived, was making

答案：

A. reached, made

B. reached, was making

C. arrived, made

(答案→)D. arrived, was making

解析：考查词汇和时态。句意：----当不明飞行物到达的时候，你在做什么？---我正在制作一杯奶昔。故选D。