undertakev.承担；从事；保证；答应undertake personally个人负担undertake a study of对 ... 进行研究undertake improvement进行改善／改进undertake an activity从事某项活动undertake an enterprise[经] 创办企业undertake the liability评判标准undertake the obligation承担义务undertake responsibility担负起责任undertake a piece of work从事一件工作undertake a glorious task肩负光荣任务

1. Don't undertake to live with your mother-in-law, but if worst comes to worst, let your mother-in-law live with you.
   千万别想到跟岳母住一起; 可是万一最坏的事情发生的话，就让岳母跟你住一起吧。
2. Do not undertake to live with your mother- in- law, but if worst come to worst, let your mother- in- law live with you.
   千万别想到跟岳母住在一起; 可是，万一最坏的事情发生的话，就让岳母跟你住在一起吧。
3. Next he undertook to pay off the debts.
   然后他同意负责偿还债务。