Phrasal idioms with the verb 'fall'

David Beckham's ......... Sir Alex Ferguson originated from his decision to stay at home and tend his ailing son rather than attend training on that particular Friday.
fall-through
fall behind in
fallback on
fallout with

Don't always ......... creating another database or a work-around program, because there may actually be a better business solution for the problem.
fall through
fall behind in
fall back on
fall out with

Frequent binge drinkers are eight times more likely than non-binge drinkers to miss a class, ......... schoolwork, get hurt or injured, or damage property.
fall behind
fall behind in
fall back on
fall off

Student mentors catch children before they ......... the cracks.
fall through
fall behind
fall back on
fall out with

The northeastern state of Assam could ......... the Indian map soon.
fall behind
fall behind in
fall back on
fall off

A Brussels-based think tank reported that Europe is ......... Asia in terms of education and skills.
falling behind
falling behind in
falling back on
falling off

She had no family support system to ........., and she couldn't afford daycare.
fall behind
fall behind in
fall back on
fall off

A recent survey showed that one in three house hunters have had a property purchase ..........
fall through
fall behind
fall back on
fall out with

Some married couples ......... each other over differences of opinion on how things could or should be done.
fall through
fall behind in
fall back on
fall out with

Deciduous trees send messages to leaves telling them when to ..........
fall through
fall behind
fall back on
fall off