Question

You’ll find it hard to get rid of the drug habit       you have it.

A．before

B．once

C．until

D．though

Answer 1

B

考查連詞，before 在什么之前，once 一旦，until 一旦，though 雖然，句意：你會發現出去吸毒的習慣很難一旦你染上。所以選B。