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,要把ie变成y再加ing,如die→dying,lie→lying.
⑥以ic结尾的动词,要把ic变成ick再加ing,如picnic→picnicking,traffic→trafficking
※注意※ 结尾是x则不必双写,如relax→relaxing