为你解答。
1、他要去上海,而不是北京。
He is going to Shanghai (instead of) Beijing
2、医生建议他这种药每天服三次。
The doctor (advised) him (to take) the medicine three times a day.
3、如果你服错了药,它可能会致你死亡。
If you (take) medicine (wrongly), it may (kill) you.
instead of
advice / advise; to take
take; wrongly; kill
第一个rather than。第二个advertised to take。