She goes stock still as Tony orders Peter to hand over the webshooters. The emptiness is close and tempting but then Peter is panicking and the glass is breaking and Tony seems to still care that Peter is hurt, even if he is angry.

She didn't need to bite her own lip to be silent. She was good at silence. Really mister Stark was partially to blame here, Peter was very very badly trained. But she's not going to offer that opinion, or any at all as she scrambles to the bag to find the tweezers. He might still be using a soft voice on her but that could all change quickly. She's not seen him angry before. She's sort of glad that she is witnessing it before it is turned on her.

Grounded. That was the punishment Peter had told her about, what would happen if she cursed in front of mister Stark. It doesn't seem like mister Stark is planning to use the weapons on Peter so...

She still is not sure what grounding is. She is still silent as she offers the tweezers to Tony, watching them both warily. She has Peter's webshooter in her bag, she had taken it off for the final climb as she figured he would be very angry if she had broken it. She says nothing though, just watches.