【正文】
preparing for my exams. 2) Would you help me make a plan to explore Beijing before he es? 3) Glad to receive your postcard. 三、課堂導(dǎo)練: 選詞填空 ,并注意其正確形式。 ( ) 1) Yesterday morning I was playing the piano ______the doorbell rang. A. when B. while C. after D. before ( ) 2) Li Lei was running______ Michael was swimming. A. when B. while C. after D. before ( ) 3) I won’t leave here until my father ______ back tomorrow. A. e B. came C. es D. ing ( ) 4) It’s about ______ from my home to school. A. twenty minutes walk B. twenty minutes’walk C. twenty m