①一般在动词原形末尾加ing,如do→doing、sing→singing、comfort→comforting
②以“不发音的e”、ue结尾的动词,先去e,再加ing,如dance→dancing、like→liking、write→writing、make→ making,take→taking
③以ee、oe、ye结尾的动词加ing,如see→seeing、toe→toeing、dye→dyeing
④以重读闭音节结尾的动词,并且末尾只有一个辅音字母,应双写这一字母※注意※,再加ing,如cut→cutting、swim→swimming
⑤以ie结尾的动词,要改ie为y再加ing,如die→dying,lie→lying
⑥以ic结尾的动词,要改ic为ick再加ing,如picnic→picnicking,traffic→trafficking