Помогите пожалуйста,нужно правельно соединить)Заранее спасибо
1.catch up with a. to have a good relationship
2.fall behing b.to begin to do something as a pastime
3. get on with c. to work hard to do uncompleted work
4.look up d. to search for a piece of information
5.go on e.to fail to keep level with another
6.take up f. to continue.