动词变现在分词,什么时候双写末尾加ing

1 一般情况下,直接在动词后加－ing
work ---- working
sleep ----- sleeping
study ----- studying
2 动词以不发音的－e结尾,要去－e加－ing
take ----- taking
make ----- making
dance ----- dancing
3
的动词,要双写词尾字母,再加－ing
cut ----- cutting
put ----- putting
begin ------ beginning
4 以－ie结尾的动词,把变成y再加－ing
lie ----- lying
tie ----- tying
die ----- dying

现在进行时和一般