I tried to walk this morning and my legs would not support me.

He tried to get up, but his legs wouldn't support him.

He tried to walk but his legs would no longer support him.

He tried to get up, but his leg would not support him.

My legs would no longer support me, and I sank to the floor.

I fell over because for some reason my legs would not support me.

But as she had feared, his legs would not support him.

He sat down suddenly, as though afraid his legs would no longer support him.

He rolled, tried to stand, and the broken leg wouldn't support him.

He tried to stand and found his left leg wouldn't support him.