please correct this for me, thanks

[jejamal]

1- responsible for / to ?
2- send to me / send me ?
3- in a scintifice article we can say :
the sample was prepared / has been prepared / had been prepared
what is the diffrence between these phrases ? would you please give some examples about these these tenses?

thanks

[Teia]

1- responsible for / to ?
2- send to me / send me ?
3- in a scintifice article we can say :
the sample was prepared / has been prepared / had been prepared
what is the diffrence between these phrases ? would you please give some examples about these these tenses?

thanks

1.answerable or accountable, as for something within one's power, control, or management (often fol. by to or for): He is responsible to the president for his decisions.[source : dictionary.com]
He is responsible for his own actions.

2. He sent me a message. ,or
He sent a message to me.

3. The sample was prepared yesterday/two days ago / last year - finished action
The sample has been prepared recently / this morning - recently finished action
The sample had been prepared before we arrived.- past action previously finished before another action in the past. "Had been prepared" shows the fact that the sample was prepared before we arrived.

I hope it helps you.