The word "can" has several synonyms that can be used to change the tone and meaning of a sentence. For example, "may" can be used to convey politeness or formality, while "able" emphasizes capability or power. "Could" indicates possibility or past ability, while "should" implies obligation or expectation. "Might" suggests uncertainty or probability, and "shall" has a more formal and authoritative connotation. Other synonyms include "be permitted to," "have the potential to," and "know how to." Choosing the right synonym for "can" can add depth and nuance to your language, and help you to better convey your intentions and meaning.