Question

【题目】There are six ________ people in the world.

A. billions of

B. billion of

C. billion

D. billions

Answer 1

【答案】C

【解析】句意：世界上有六十亿人。hundred, thousand, million前有数词时，表示实指，hundred, thousand, million用成单数形式；表示虚指时，hundred, thousand, million后跟介词of，hundred, thousand, million用复数形式。本空前有six，表示实指，billion用单数形式。故选Ｃ。