how to use two dsl line with on 433 routerboard

RouterOS Beginner Basics
1

Can anyone tell me if this is possible and how its done if it is.

2

Do you want to use them:

Independently?
Failover?
Load balancing?

3

loadbalancing please

4

Setup a gateway for ecmp
http://wiki.mikrotik.com/wiki/Manual:IP/Route#Multipath_.28ECMP.29_routes

and then prepare something for failover:
http://wiki.mikrotik.com/wiki/ECMP_Failover_Script
http://wiki.mikrotik.com/wiki/Improved_Netwatch_II

For failover there is another solution in Mikrotik wiki, but for now I didn’t try it:
http://wiki.mikrotik.com/wiki/Advanced_Routing_Failover_without_Scripting