Cars moved very slowly in the 1930s,but they A faster than in the 1920s.
问题描述：
Cars moved very slowly in the 1930s,but they A faster than in the 1920s.
A.did move B.had moved
C.would move D.were moving帮忙解决
答
A.did可省把move加d,但这里加个did是强调的意思