外语题,
问题描述：
外语题,
急求英语中变现在进行时+ing要双写最后一个字母的单词,越多越好,50个以上再给10分!
动词的现在分词，还有，我是让举例子！
答
run swim put get sit dig refer prefer travel quarrel begin forget stop beg admit defer
cut shut step permit spin hit stir rob plan win
strug nod tap drop slot slug shop shot slip sob