Complex sentence: At about two to four months infants begin to develop hand-eye coordination marking the beginning of a trial and error period, where infants randomly try to grasp objects that cannot be grasped like pictures and object that can like toys.
Split into simpler sentences: At about two to four months infants begin to develop hand-eye coordination. This marks the beginning of a trial and error period, where infants randomly try to grasp objects that cannot be grasped like pictures and object that can like toys.