But inside, special windows cut power bills by blocking solar heat in summer and retaining indoor warmth in winter.
出自-2013年6月閱讀原文
"For once, we are the ones who are blocking the traffic," he says delightedly.
2018年6月四級真題（第二套）閱讀 Section B
with the right device tuned to the right frequency, what's to stop a thief from jamming your setup and blocking that alert signal from ever reaching the base station?