一、分析与理解：

in and around the small town其实是in the small town and around the small town 的简洁表达，意思是“在小镇及其周边”。所以句意就是：Students from seven different primary schools in and around the small town were warming up and walking the route through thick evergreen forest. 来自小镇及其周边的七所不同小学的学生正在热身并要步行穿过茂密的常青森林。

二、更多例句如：

Most development has been concentrated in and around cities. 土地开发主要集中在城市及周边地区。

There was savage fighting in and around the eastern border towns. 东部边境城镇及其周边地区在发生恶战。

Fighter bombers are attacking key installations in and around the city. 战斗轰炸机正在轰炸市内及四周的关键设施。

Rivers, and observedly the rivers in and around the cities, have been polluted. 河流，尤其是城市内及其周围的河流，都受到了污染。

三、更多相关用法：

1. in and out of

He drifted in and out of sleep all night. 整夜他时睡时醒。

He was drifting in and out of consciousness. 他一会儿醒过来，一会儿又昏过去。

He’s been in and out of hospital all year. 他一整年经常入院出院。

Flights in and out of Paris are functioning normally again. 进出巴黎的航班又恢复正常了。

2. to and from

When we were children, we used to walk five miles to and from school every day. 我们孩提时代每天都要步行五英里上学和回家。

Local buses run regularly to and from the nearest town. 当地有往返最近城镇的班车。

The children need to be ferried to and from school. 孩子们上学放学需要摆渡。

Transport to and from the airport is included in the price. 价格中包括往返机场的交通费。

A van at the hotel transports guests to and from the airport. 宾馆有辆面包车接送往来于机场的客人。

On Saturday morning all flights were cancelled to and from Glasgow. 星期六上午往返于格拉斯哥的所有航班都取消了。

3. up and down

They cruised up and down the coast road. 他们在滨海道路上开着汽车来回兜风。

He continued to hump cases up and down the hotel corridor. 他一直在旅馆走廊上下搬运箱子。

He paced up and down the room, looking worried. 他在屋里踱来踱去，显得焦虑不安。

We up and down the town’s main drag looking for a post office. 我们在大街上走来走去找邮局。

4. on and off

She's old and needs help getting on and off the bus. 她年纪大了，上下公共汽车需要帮助。

Players need discipline both on and off the field. 运动员在场内场外都须遵章守纪。

Stop switching on and off the light that way. 别把灯的开关那样开开关关。

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