那个男孩对新的知识吸收很快。

[误] The boy absorbs in new knowledge quickly.

[正] The boy absorbs new knowledge quickly.

[正] The boy absorbs into new knowledge quickly.

[正] The boy takes in new knowledge quickly.

注：absorb(吸收)是及物动词，可以直接跟宾语，absorb in 的意思是“吸引，专心于”，absorb into 才是“吸收”，另外 take in 也表示“吸收”。