问题补充：
Won’t you me in a walk after supper? It will do good to your health, you know.
A. join in
B. join
C. participate in
D. take part in
答案：
A. join in
(答案→)B. join
C. participate in
D. take part in
解析：join in\ participate in \take part in的宾语是物而join的宾语可以是人。 晚饭后加入我的散步活动吗？你知道这对健康有好处。 因为“加入“的宾语是人所以答案为B
