Question

Remember to         your mobile phone when the plane takes off.　　
A. turn on       B. turn down       C. turn off　　

Answer 1

C

詞義辨析。turn on 打開；turn down關(guān)小，調(diào)低；turn off關(guān)閉。句意：當(dāng)飛機(jī)起飛時(shí)記得關(guān)掉手機(jī)。所以選C。