Americans eat _____vegetables per person today as they did in 1910.
A.more than twice
B.as twice as many
C.twice as many as
D.more than twice as many

选什么,为什么？

选D。

倍数表示法有如下四种：
1,…+数字(或倍数)+比较级+than…。如：The is room is three times larger than that one．(这个房间比那个大三倍。)

2,……倍数+as+形容词或副词+as+…。如：A is twice as long as B．A的长度是B的两倍。

3,…+by+数字(或倍数)+…。如：This ruler is longer than that larger by 2 inches(或by twice)．(这把尺子比那把尺子长二英寸(或两倍)。)

4,…倍数+the size(height,length,width etc．)of+…。如：The river is five times the length of that stream．(这条河有那条小溪五倍长。)

所以D为正确答案。