对下列二叉树 进行中序遍历的结果是( )。 A．ACBDFEG B．ACBDF

Read and draw. 阅读短文，请将文中划线单词的序号标注在图中相应位置。 

     This is Ann's bedroom. It's very nice. Her schoolbag is behind the chair. Her pencil is on the

                                                                           A                                              B

desk. Can you see a football in the room?  No, I can't. I can see a picture on the wall beside 

                                                                                                        C

the door. What's under her bed? It's her book. It's very new.

                                                                D

有一种新型可降解塑料，其主要成分是聚乳酸，可在微生物的作用下自然分解，使用这种塑料制品主要可以减少[ ]

A．土壤污染

B．大气污染

C．水污染

D．生物污染

视网膜劈裂症最常出现的部位是（）

A.鼻上象限

B.鼻下象限

C.颞上象限

D.颞下象限

E.黄斑区

根据《旅馆业治安管理办法》，在接待境外旅客住宿时，旅馆除应查验旅客身份证件，如实登记规定项目外，还应该在（）小时内向当地公安机关报送住宿登记表。

A.12

B.24

C.36

D.48

“戈森定律”认为人的某种欲望会随其不断满足而（）。

A.递减

B.递增

C.不变

D.有时递减，有时递增