be busy后接不定式還是現(xiàn)在分詞

be busy后習(xí)慣上要接現(xiàn)在分詞，不能接不定式。如：

She’s busy writing letters. 她正忙著寫信呢。

She was busy preparing lessons. 她忙于備課。

He was busy packing, for he was leaving that night. 他那時(shí)正忙著打點(diǎn)行李，因?yàn)槟翘焱砩纤�就要走了�?/SPAN>

順便說一句，busy用作動(dòng)詞時(shí)，通常用于busy oneself doing sth，其中的現(xiàn)在分詞也不能換成不定式。如：

He busied himself cooking the dinner. 他忙著做飯。

She busied herself tidying up her desk. 她忙著收拾她的寫字臺(tái)。

注：有時(shí)可在現(xiàn)在分詞前加上介詞in，這樣一來現(xiàn)在分詞就變成了動(dòng)名詞。如：

She was busy in preparing lessons. 她忙于備課。

He busied himself in cooking the dinner. 他忙著做飯。