The dollar dropped against the euro and the pound but rose against the yen Wednesday as traders, concerned about the U.S. economy, awaited a key address by Federal Reserve Chairman Alan Greenspan later this week. "The near-term trend seems to be tilting somewhat toward dollar weakness," said Kenji Kobayashi, senior foreign exchange manager at Bank of Tokyo-Mitsubishi. "The dollar seems to be sinking under its own weight." Forecasts for a weaker U.S. economy usually hurt the dollar, as investors shift cash from U.S. securities to other markets.