He leaned against the wall, and felt his knees growing weak beneath him.

I could feel my knees collapse and then nothing.

Burning Tower felt her knees shaking as she sat again.

I can feel my knees a little bit more.

Finally, instead, he kept himself under control, although he could feel his knees trembling.

She heard him and he felt her knees pressing between his thighs.

The girl was feeling her knees, running her hands back and forth across them.

She shoved back from the table feeling her knees gone jellylike.

I can't feel my knees anymore and the sky begins to spin.

Miss Mahan felt her knees giving way and quickly sat down.