美国股指期货跌幅扩大，标普500指数期货下跌1.4%

Group 1 - The core point of the news is that U.S. stock index futures have seen a significant decline, with the S&P 500 index futures dropping by 1.4% [1] Group 2 - The news indicates a broader trend in the market, as the decline in stock index futures may reflect investor sentiment and potential economic concerns [1]