[事「こと」]だ => A is necessary/good (offering advice/suggestion) N3
Needs, Requirement
[代「か」]わり => Not A, but B, B in place of A, Instead of A, B; In exchange for A, B N3
Comparison, Exchange
[事「こと」]ができる => Be able to A; can do A, Can A; be possible to A; N4
Causative, Passive, Volitional
に[限「かぎ」]った[事「こと」]ではない => It's not limited to A, it's not only A N1
Degree/ Level/Amount