彼の丁寧な説明を聞いて、ようやく得心がいった。
After hearing his careful explanation, it finally made sense to me.
何度話し合っても、父は得心しなかった。
No matter how many times we talked it over, my father was not convinced.
双方が得心するまで条件を詰めることにした。
We decided to work out the terms until both sides were satisfied.