对如下二又树，进行后序遍历的结果为 A．ABCDEF B．DBEAFC C．A

Upon their entering the tomb, Carter’s lucky pet bird, which he ____ in Cairo, was swallowed by a snake.

A．was left

B．had left

C．left

D．was leaving

— You look beautiful(漂亮).

— ________.

A. Thanks you    B. Thank you    C. Me,too

We had intended to do everything according to the schedule, but it didn’t               ______ as planned.

A．make up

B．turn out

C．go on

D．come up

秋季腹泻最常见的病原体是（）

A.金黄色葡萄球菌

B.大肠埃希菌

C.耶尔森菌

D.轮状病毒

E.柯萨奇病毒

分光光度法测定样品的基本原理是利用朗伯—比尔定律，根据不同浓度样品溶液对光信号具有不同的（），对待测组分进行定量测定。