问题补充：
The competition is fierce .No women or children are allowed to .
A. join
B. take part in
C. compete for
D. join in
答案：
A. join
B. take part in
C. compete for
(答案→)D. join in
解析：join后面加组织，take part in（积极）参加（活动），compete for为…竞争，join in 参加（活动，比赛）。句意是：比赛很激烈，妇女儿童不允许参加。选D。
