~やむをえず  => unavoidable, no other way to do something N2
Necessity, obligation
てやる => Do for someone N4
Give and take advice
やる => Give B to A N4
Give and take advice
...を...みる => judging from; seeing that ~ N4
Deduce
...を...にする => to make something ~ N4
Purpose, target
姿を見せる => figure; appearance N3
Ability
や => ... or... N5
Line up, list
... るや => at the sight of; upon seeing; right after confirming ~ N1
Short period of time
や否や => as soon as; the moment ~ N1
や、やいなや => As soon as A, B N1
Time, Situation
...が...を...みせる => make it look like... N4
Base, base
を…とする => is considered, is regarded as N2
Consider it