According to a temperature analysis conducted by scientists at NASA, the average global temperature on Earth has increased __________.
A、overtime
B、over time
C、in time
D、from time to time
全新版大学进阶英语：综合教程第一册

章节列表

Unit 01 The Pursuit of Dreams53Unit 02 Freshman Year53Unit 03 True Stories of Nazi Germany54Unit 04 Meeting Statesmen54Unit 05 The Water Problem53Unit 06 Going Offline54