如图所示，一条水平长直轨道上有两辆小车，甲车向左做匀速直线运动，速度大小为 $v_1$，乙车向右做匀速直线运动，速度大小为 $v_2$，甲车上装有一支枪，每隔 $\Delta t_0$ 时间水平射出一颗子弹，都能击中装在乙车上的靶子，不计子弹的重力和空气阻力，每颗子弹对地速度保持 $v_0$ 不变，每颗子弹击中靶时下一颗子弹已经射出，设两车速度不受子弹射击影响，求： (1)(3分)空中相邻两颗子弹间距离 $x$； (2)(6分)相邻两颗子弹击中靶的时间间隔 $\Delta t$ 的大小。

双人跳水比赛时，甲、乙两运动员起跳后由于不同步，甲运动员先入水，在下落过程中某时刻，甲运动员看到乙运动员正在上升，则该时刻 A. 甲运动员选用的参考系为看台 B. 甲运动员选用的参考系为乙运动员 C. 甲运动员选用的参考系为自己 D. 以水面为参考系，甲运动员向上运动

语法填空： 1. I can't wait ________ (start) my new senior high school journey. 2. Senior high school life is full of ________ (challenge) and new chances. 3. We should rise to the challenges ________ (face) us in our new study life. 4. The key to ________ (realize) your potential is continuous hard work. 5. He is responsible ________ organizing all the after-school activities in our class. 6. Keeping a positive mind helps us ________ (overcome) difficulties in study. 7. Every student has the potential ________ (become) a well-rounded person. 8. Success lies in ________ (stick) to your goals and never giving up. 9. We should take advantage of school resources ________ (improve) our abilities. 10. Confidence is one of the most ________ (value) qualities for senior high students.

一、词性转换 1. challenge n. 挑战 $\rightarrow$ ______ adj. 有挑战性的 2. responsible adj. 负责的 $\rightarrow$ ______ n. 责任；职责 3. advance v. 进步；前进 $\rightarrow$ ______ adj. 先进的；高级的 4. effort n. 努力 $\rightarrow$ ______ adj. 费力的；艰难的 5. confidence n. 信心 $\rightarrow$ ______ adj. 自信的 6. profession n. 职业 $\rightarrow$ ______ adj. 专业的；职业的 7. acquire v. 获得，得到 $\rightarrow$ ______ n. 取得；获得；得到的东西 8. individual n. 个人 $\rightarrow$ ______ adv. 个别地；单独地 9. senior adj. 年长的；高级的 $\rightarrow$ ______ n. 年长；资历 10. equal adj. 相等的；平等的；相当的 $\rightarrow$ ______ n. 平等；相等

I ______ (毫无疑问) that you will succeed if you work hard.

She decided to ______ ______ (报名参加) the English club.

Dear Jack, I remember the moment — it truly hit me that your autism(自闭症) lasted forever. I had already mentally planned our trips up north with the boys. I was going to spend endless hours playing baseball with you — like Grandpa did with me. When we said goodbye to kindergarten I knew it was real. I spent some time being sad. Now you are 8. You still have no words. We have never had one of those father-son moments I pictured when you were a baby. But I'm learning that's OK. I still have unbelievable things to offer as your dad, even if they weren't the things I originally expected. You have taught me to be patient. You have taught me that it's OK to be different and to be sad when life doesn't go as planned. You have taught me that it is OK to talk about those feelings and fight for what is right. Stand up and say this is wrong, and encourage others to stand up for you and say the same. My job on this earth is to create a world for you and other kids like you. Be the voice you don't have, and build the kind of community which I want to see you grow up in. I used to shy away from contacting people with disabilities or just not consider them. Before you were born, I was so caught up in my own world that I probably wouldn't have even noticed. Now, I see things differently. I notice. You did that for me. And hope my example will do that for others. Your mom and I have spent 8 years trying to find your voice. And honestly, we don't know if we ever will. I promise you I will spend my life keeping you safe and making this world better for you. What can be learned about the author? A. He is at a loss what to do to help Jack. B. He is to blame for Jack's present condition. C. He has changed his attitude to the disabled. D. He hasn't accepted the reality up to now.

设 $M$、$P$ 是两个非空集合，定义 $M$ 与 $P$ 的差集为 $M-P=\{x \mid x \in M \text{ 且 } x \notin P\}$，则 $M-(M-P)$ 等于 ( ) A. $P$ B. $M$ C. $M \cap P$ D. $M \cup P$

设集合 $M$ 为实数集 $\mathbf{R}$ 的非空子集. 若对任意 $x, y \in M$，都有 $x+y, x-y, xy \in M$，则称 $M$ 为封闭集. 以下结论正确的有 A. $M = \{x \mid x = a + \sqrt{2}b, a, b \in \mathbf{Z}\}$ 为封闭集 B. 若 $M$ 为封闭集，则一定有 $0 \in M$ C. 若 $M$ 为封闭集，则满足 $M \subseteq T \subseteq \mathbf{R}$ 的任意集合 $T$ 也是封闭集 D. 存在集合 $A \subseteq \complement_{\mathbf{R}}\mathbf{Q}$，$A$ 为封闭集

集合 $A = \{x \mid -12 \le x \le 15\}$，集合 $B = \{x \mid m+1 \le x \le 2m-1\}$，若 $A \cap B \ne \emptyset$，则实数 $m$ 的取值范围是______