1、Stefan's off the rails.
斯特凡已经失常了。

行为失常;发疯;走上错误的道路

e.g: At 17 he suddenly went off the rails and started stealing.
17岁他突然不务正业开始偷盗。

2、The sheriff has me slip it into the coffee here every now and then.
警长让我时不时地在咖啡里加一些(马鞭草)。

every now and then/again = every so often
不时地;偶尔

e.g: I still see her every now and then.
我任然偶尔能见到她。

3、I don't know why you think that you're a lost cause.
我不明白为什么你觉得自己是个失败者。

注定失败;没有成功的机会

e.g: Trying to interest my son in classical music is a lost cause.
让我儿子对古典音乐感兴趣一定不会成功的。

4、Bottoms up.
干了吧。

干杯

5、He's flipped the switch.
他已经完全失控了。

flip a switch
开/关开关。剧本中是比喻义。

e.g: You start the fan by just flipping this switch.
拨这个按钮就能打开电风扇。

6、Did you miss the part where I checked out of all this?
你该不会是忘了我已经撒手不管了。

这里是比喻义,表示不再插手某事

e.g: I'm not the kind of person who checks out.
我不是那种会撒手不管的人。

7、Yeah, but Damon's not exactly in the mood to help right now.
可是达蒙现在根本就没心情帮忙。

愿意做某事;想要做某事

e.g: I don't want to talk about it now. I'm not in the mood.
现在我不想谈论此事,没那个心情。

8、Yeah, but he's still holding on to his humanity, which means he can still be saved.
没错,可他仍然人性未泯,这说明他还有的救。

保持;不放弃

e.g: The soldiers held on to the bridge for three more days.
士兵们坚守着这座桥三天多。

9、Look, he would never give up on me. I'm not gonna give up on him.
他永远不会放弃我,我也不会放弃他。

放弃;对...不再期望;对...绝望

e.g: He'd been in a coma for six months, and doctors had almost given up on him.
他昏迷了6个月,医生几乎对他不抱有什么希望了。