practice是以e結尾的動詞，通常去e加ing，所以practice的ing形式是practicing
一般情況下，直接在動詞後加－ing work ---- working sleep ----- sleeping study ----- studying
動詞以不發音的－e結尾，要去－e加－ing take ----- taking make ----- making dance ----- dancing
重讀閉音節的動詞，要雙寫詞尾字母，再加－ing cut ----- cutting put ----- putting begin ------ beginning 以－ie結尾的動詞，把變成y再加－ing lie ----- lying tie ----- tying die ----- dying
