I have stumbled onto two sentences in my book and I wonder to know why there is missing "his" before "tears" and "a cople of feet". The texts are
Then, as he tried to drop a couple of feet to the ground, he caught his shirt on a metal shard that hang him up for an instant before tearing loose.
Chad fought tears as he leaned in and pressed his head against his father's chest.
For me it would be OK to say "his tears" and "his couple of feet", because it was his tears and his feet, as well as it was his shirt and his head, but I think it was reason for writer not to write that. Can you explain to me why?