1) He was busily engaged writing letters.
他正忙於写信。
2) He is busy with his writing.
他忙於写作。
3) He was busily engaged in writing letters.
他正忙于写信。
4) He is busily engaged in writing a thesis.
他正忙着写论文。
5) He is busy in writing his love letters
他正忙着写情书。
6) He' s busy copying the letters.
他忙于缮写信件。
补充资料：我们
1.代词。称包括自己在内的若干人。
说明：补充资料仅用于学习参考，请勿用于其它任何用途。
参考词条