---Will it be a long time I come for the pictures?--No. It be ready by 3:00A. that;

问题补充：

---Will it be a long time I come for the pictures?

----No. It be ready by 3:00．

A. that; can

B. since; will

C. before; should

D. until; must

答案：

A. that; can

B. since; will

(答案→)C. before; should

D. until; must

解析：考查固定句型和情态动词：第一空填before，用It will be+一段时间+before…,要过多久才…,第二空填should表示按道理应该，句意：我还要很长时间才能拿照片吗？--不用，到三点应该可以拿到了。选C。