Bernie Sanders took to social media to share his two cents while Donald Trump spoke at the Republican National Convention in Cleveland on Thursday. During his speech, Trump said that Sanders supporters would be joining his movement — but Sanders didn't exactly agree. First, he tweeted, "Is this guy running for president or dictator?" Later, he added that his supporters wouldn't be on board with the Republican candidate, tweeting, "Our movement understands that what we don't need is Trump's huge tax breaks for millionaires." Keep reading for a look at some of Sanders's must-read tweets about the RNC, then catch up on all our Republican National Convention coverage.