Each of these answers is the title of a Grateful Dead song with lyrics written by John Perry Barlow,
but missing a single word:
- looks LIKE RAIN
- BLOW away
- SALT LAKE city
- estimated PROPHET
The added words are
- looks
- away
- city
- estimated
which together spell the answer LACE, as in "Crazy cat peekin' through a lace bandanna", in the
(non-Barlow-authored) Dead song "China Cat Sunflower".