病例对照研究的研究方向是（）。 A.由因到果 B.由果到因 C.描述因和果在某一时点

某初产妇，35岁，对其进行B超测量骨盆结果是：入口平面前后径11cm，横径13cm；中骨盆横径9.5cm，前后径11.5cm；出口横径7.5cm，后矢状径8cm。

该产妇是否可以试产，如果可以，试产的时间是（）

A.不可试产

B.可试产，1小时

C.可试产，1.5小时

D.可试产，2小时

E.可试产，4小时

下列四种现象中，属于光的反射现象的是：[ ]

A.

B.

C.

D.

两个奇数的和还是奇数．______．

除石膏种类外，影响石膏强度的因素还有石膏的（）等。

(B)

When I was six, Dad brought home a dog one day, who was called "Brownie". My brothers and I all loved Brownie and did different things writh her. One of us would walk her, another would feed her, then there were baths, playing catch and many other games, Brownie, in return, loved each and every one of us. One thing that most touched my heart was that she would go to whoever was sick and just be with them, we always felt better when she was around.

One day, as I was getting her food, she chewed up one of Dad’s shoes, which had to be thrown away in the end. I knew Dad would be mad and I had to let her know what she did was wrong. When I looked at her and said, "Bad girl," she looked down at the ground and then went and hide. I saw a tear in her eyes.

Brownie turned out to be more than just our family pet, she went everywhere with us. People would stop and ask if they could pet her. Of course she’d let anyone pet her. She was just the most lovable dog. There were many times when we’d be out walking and a small child would come over and pull on her hair. She never barked or tried to get away. Funny thing is she would smile. This frightened people because they thought she was showing her teeth. Far from the truth, she loved everyone.

Now many years have passed since Brownie died of old age. I still miss days when she was with us.

What would Brownie do when someone was ill in the family（）

A. Look at them sadly.

B. Keep them company.

C. Play games with them.

D. Touch them gently.