Yes, broad base refers to index funds with wide coverage and strong representation, such as Shanghai Composite Index, Shanghai and Shenzhen 300 Index, China Securities 500 Index, Growth Enterprise Market Index and other related funds.

Wide-base corresponds to narrow-base, which is an index fund introduced to a certain industry or sector, such as consumer ETF, brokerage ETF, medicine ETF, food ETF and so on. Both broad and narrow funds belong to passive funds.