I am really confused on the this topic, could someone please help? In a phrase like,"Come on up." I know "up" modifies "come on." What happens when you are able to switch positions of adverbs and adverbials? In, "I played yesterday at the park.", and "I played at the park yesterday." Does "yesterday" modify "played at the park" in both or does "at the park" modify played yesterday in the first sentence?