Sentence 1 suggests that the explanation is about something "sensible", as in it is practical or reasonable and that "he" would understand the explanation was wise or prudent. It also suggests "he" was not being sensible before. One example would be someone persuading his friend to not buy an old car.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.
napoleonponapa1) After a while of his mother's explanation, he comes to his senses.(The past "came to his senses", makes more sense, but present is conceivable). THe first phrase is not natural:
After his mother had explained at some length, he came to his senses.
After a lengthy explanation from his mother, he came to his senses.
2)