הרבה - either "a lot" in the sense of quantity, or sometimes "often" as in "a lot of times". For example: יש הרבה ספרים בבית שלהם. There are a lot of books in their house. אנחנו הולכים הרבה ברגל We go a lot/often by foot. הוא נוסע הרבה לירושלים. He goes (by vehicle) a lot/often to Jerusalem. === כל כך - "so much", or "so" in the same meaning. .הוא אהב כל כך את הסרט הזה He liked that movie so much. הם התרגשו כל כך. הם כל כך התרגשו. They were so excited/moved. === מאוד - "very" when used with adjectives, although it can be used with verbs in a similar way to kol kakh but slightly less strong, like "very (much)" (as opposed to "so much"). בקיץ חם מאוד. It's very hot in the summer. הם התרגשו מאוד. הם מאוד התרגשו. They were very excited/moved.