What is the meaning of "ve'Orishenu"?
Rashi: It means "And I will drive them out!" 1
Seforno: It means 'And I will dispossess them' - and pass on the inheritance to their children. 2
Targum Onkelos and Targum Yonasan: It means 'And I will destroy them!'
The Gur Aryeh does not have the word 'ke'Targumo' in Rashi.
Why did Hashem need to inform Moshe that He would make him into a great nation?
Rashi: This was necessary to avoid the question what would happen to the promise that Hashem made to the Avos. 1
The question arises however, why this was necessary - seeing as the children below the age of twenty were not punishable and there was no reason to kill the tribe of Levi - who had not sinned.