"Threw in" is a phrasal verb that means to add something to a situation or discussion. There are various synonyms for this expression, such as "contributed," "included," "offered," "tossed in," "pitched in," "put in," "submitted," "entered," "donated," "added," "injected," "supplied," or "brought to the table." Each of these words conveys a slightly different shade of meaning, but they can all be used as alternatives for "threw in." Whether you are writing a formal report or having a casual conversation, using these synonyms can help you broaden your vocabulary and express your ideas more precisely.