palmar grasp is where an infant holds an item such as a crayon with the palm of their hand, where as the pincer grasp is where they hold it between their thumb and index finger (more sophisticated)
"Its" is a possessive pronoun of "It". Example: Its rear tire is out of balance. "It's" generally translates to "It Is" or "It has". Example: It's about time you got home.
"Explain" means to give additional information, such as details, rationales, or other clarification of an existing issue. It implies teaching, instruction, or the reiteration of knowledge.
"Discuss"...