选择做
what's that "should they so choose" doing there?───在那儿“他们应该选择的”那样是什么？
Hence, steps describe units of work within the task that the task performer can choose from when doing the work.───因此，步骤描述了任务执行者可选择的任务中的工作单位。
they've started doing DNA tests on kids to choose their careers.───他们已经开始在儿童身上做DNA测试，来给他们选择职业。
And what's that "should they so choose" doing there?───在那儿“他们应该选择的”那样是什么？
chase down───找出
choke down───强咽下去；抑制
choosing───v.选择；决定（choose的ing形式）
chops down───砍下
close down───关闭；停止播音
close downs───关闭；停止播音
hose down───用水管浇
chocolate pudding───巧克力布丁
-choosing───v.选择；决定（choose的ing形式）