Question

CCTV is exactly like a window on the world ________ you will sit by it and fix your attention on what it shows.

1. A.
   if
2. B.
   as
3. C.
   while
4. D.
   unless

Answer 1

A
if引導(dǎo)狀語從句表示一個假設(shè)。 假如你坐下來看節(jié)目，就會了解這一點。