1.   Both were known to push the envelope of life.

2.   In one entrapment incident when he was in the Assembly, some one pushed an envelope under his door.

3.   It needs some one who understands its basic talent, some one who will help it to push the envelope of its artificial intelligence.

4.   He will continue to push the envelope of what is possible.

5.   American TV has been pushing the envelope of taste to the tearing point for the past few years.

6.   An equally robust defense bar will push the envelope back in the opposite direction.

7.   And I thought our relatives were pushing the envelope of sanity by amassing frogs and bunnies.

8.   And despite their flaws, the filmmakers were willing to push the envelope of cinema and deserve an audience.

9.   And nowhere have radiologists had more success in pushing that envelope than in Boston.

10.   And some critics wonder how safe it is when desperate patients encourage eager researchers to push the envelope of what is possible.