答案：B

题目分析：因为这个句子已经有谓语动词，句子中又没有连词故空格处应用它的非谓语动词，people与 take part in之间是主动关系，故选B.

点评：非谓语动词是高中的重难点之一，也是高考常考点，需要考生平时牢牢掌握它的用法。

即学即练：The students       a school activity must  gather at the main gate of our school at seven thirty.

A. were taking part in              B. taking part in

C. taken part in                   D. took part in

解析：B 句意：参加学校活动的学生必须在7:30在学校大门口集合。