题目内容
When Tom knocked at the door, I was busy ________ my homework and my brother was busy ________ a model plane.
A. to do; with B. doing; with doing
C. with; making D. with; to make
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题目内容
When Tom knocked at the door, I was busy ________ my homework and my brother was busy ________ a model plane.
A. to do; with B. doing; with doing
C. with; making D. with; to make