答案B
介词by后接表时间的名词,意为“在……之前”如:I have to go back by ten o'clock.我必须在10点钟以前回去.Will you please finish the work by Friday? 请你在星期五之前完成这份工作好吗?
答案B
介词by后接表时间的名词,意为“在……之前”如:I have to go back by ten o'clock.我必须在10点钟以前回去.Will you please finish the work by Friday? 请你在星期五之前完成这份工作好吗?