阅读下面的短文，理解其大意，并从 A、B、C 三个选项中选择出一个能填入空白处的最佳选项。
Hallway Rules: Keep Safe and Orderly
School hallways are the busiest places in our school, especially between classes. Following hallway rules is very important. These rules $\underline{1}$ us stay safe
and make the hallways a nice place for everyone. Here are the hallway rules.
Walk in a Right Way
When you are in the hallway, you $\underline{2}$ run or chase(追逐) your classmates. You must walk $\underline{3}$ and carefully. Running is so $\underline{4}$ —you may bump(碰撞) into other students and fall down. You also have to keep to the $\underline{5}$ side of the hallway. This helps all students walk through quickly without pushing.
Keep Quiet and Polite
Talking loudly or shouting in the hallway is not allowed. You $\underline{6}$ keep quiet because many students are going to their next classes. When you meet your teachers or classmates, you should say "Hello" $\underline{7}$ them politely. If you need to get past others, say "Excuse me" first.
Take Care of Your Things
If you carry books, schoolbags or other things, hold them carefully. You $\underline{8}$ throw anything in the hallway, or swing your heavy bag around. It may hit someone by accident. And never leave your things on the floor—it will block(挡住) the way for others.
Follow the Rules Always
All these hallway rules are easy to follow. $\underline{9}$ you break the rules, you may get a warning from your teacher. These small rules make our school life $\underline{10}$. Remember:No rules, no order! Let's follow hallway rules together.
()1. A. help B. show C. want
()2. A. can B. mustn't C. have to
()3. A. fast B. quickly C. slowly
()4. A. safe B. dangerous C. interesting
()5. A. right B. left C. middle
()6. A. must B. can C. mustn't
()7. A. for B. to C. with
()8. A. can B. must C. mustn't
()9. A. If B. But C. And
()10. A. higher B. better C. worse

1.A 2.B 3.C 4.B 5.A 6.A 7.B 8.C 9.A 10.B

本题是校园走廊规则主题的完形填空，结合上下文语境和七年级所学的词汇、固定搭配逐一分析：
1. 句意：这些规则帮助我们保持安全，也让走廊对所有人来说都成为舒适的场所。固定搭配help sb. do sth. 表示“帮助某人做某事”，show（展示）、want（想要）不符合语境，选A。
2. 句意：当你在走廊里的时候，你不准跑或者追逐你的同班同学。mustn't表示“禁止，不准”，符合走廊安全规则的要求，can（可以）、have to（不得不）不符合，选B。
3. 句意：你必须慢慢走，小心走。slowly意为“缓慢地”，符合走廊通行的安全要求，fast（快地）、quickly（迅速地）不符合规则逻辑，选C。
4. 句意：跑步是很危险的——你可能撞到其他同学然后摔倒。dangerous意为“危险的”，对应后半句描述的不良后果，safe（安全的）、interesting（有趣的）不符合，选B。
5. 句意：你也必须靠走廊的右侧通行。靠右行是公共通行的常识，能避免拥堵，right（右边的）符合语境，left（左边的）、middle（中间的）不符合，选A。
6. 句意：你必须保持安静，因为很多学生正要去上下一节课。must表示“必须”，符合规则要求，can（能够）、mustn't（禁止）不符合语境，选A。
7. 句意：当你遇到你的老师或者同学，你应该礼貌地向他们说“你好”。固定搭配say hello to sb. 表示“向某人问好”，选B。
8. 句意：你不准在走廊里扔任何东西，也不要把你的重书包到处甩。mustn't表示“禁止”，符合安全要求，can（可以）、must（必须）不符合，选C。
9. 句意：如果你违反规则，你可能会收到你老师的警告。if引导条件状语从句，意为“如果”，符合逻辑，but（但是）、and（和）不符合，选A。
10. 句意：这些小规则让我们的校园生活更好。better意为“更好的”，符合遵守规则的积极意义，higher（更高的）、worse（更差的）不符合语境，选B。