I think I'd better go now.
我想我最好现在就走。
I came last but one in the race.
我赛跑得了倒数第二名。
I like to be on my own sometimes.
有时候我喜欢一个人待着。
I don't feel I've accomplished very much today.
我觉得我今天没干成多少事。
I never realized you could be so calculating.
我真没有想到你会这样有心计。