Question

（）sales of cars up by 30% last year, the traffic in Beijing

Answer 1

因为 sales of cars up by 30% last year是复合宾语,不是句子

能接复合宾语的介词只有with

sales of cars(介词宾语） up（副词做宾补） by 30% last year（状语）

如果用As,要说：

As sales of cars【 was】 up by 30% last yea