to do [动词] 做 Ex: I 'm not sure what to do in this situation ; it 's quite confusing . 我不确定在这种情况下该做什么;这很令人困惑。
to sing [动词] 唱歌 Ex: During the car ride , they sang to keep themselves entertained . 在乘车途中,他们唱歌以自娱自乐。