Collocations with gap

: Which of the following is a common collocation that describes

? N1. a big gap
a wide gap
a broad gap
an open gap

? N2. the gap between older and younger people
the generation gap
the generational gap
the gender gap

? N3. A gap that cannot be closed
an unbridgeable gap
an uncrossable gap
an uncloseable gap

? Which word best completes the sentence

N4. He was twenty years older than her, but they seemed very happy despite the ________ gap
age
ages
years

N5. The focus of economic policy had been to _____ the gap between the rich and the poor
bridge
tighten
lower

N1. Wide gap
N2. the generation gap
N3. an unbridgeable gap
N4. age
N5. bridge