Please help

I just buy my first mpc and I want to ask a question... I drop samples to one senquence and when I push first pad and the secound pad right after they are playing together... I want to play pad 1 and when I push pad 2 the pad 1 will stop play ... how do I do that ... sorry for bad english

Set your program to mono.

but it only works on single pads and the pads cant be combinated... when i push A1 - A1 - it works , but when i push A1 - A2 its not working...

can somebody help me with that ?

You need to check the program section of the manual to fully understand the ways of setting up pads.

You need to set the Pads to the same Mute Group to achieve this :

1) Select Program Mode, then scroll the Data wheel until you reach Mute Group
2) Hit the pad you wish to apply Mute Group to
3) Using Cursor button to navigate to OFF and scroll Data wheel to select group (say 1 for example)
4) Hit the second pad you wish to apply Mute group to and select same group as the first pad (group 1)

When you now hit the first pad and then the second pad straight after, the sound from first pad should disappear.

This is detailed on page 79 of manual, which is an absolute must read to learn all these features.
Plus practise, practise, practise !