Send me a letter as soon as you arrive so that I won't worry. 到了就来信,省得我挂念。
Let me remind you once again so that you won't forget. 我再说一遍,省得你忘了。
牛津高阶第八版
美国韦氏词典
Dictionary.com
Free Dictionary
维基百科 (自由的百科全书)