Complex sentence: Nkrumah had sought entry to Lincoln some time before he began his studies there; on 1 March 1935, he had sent the school a letter noting that his application had been pending for more than a year.
Split into simpler sentences: Nkrumah had sought entry to Lincoln College some time before he began his studies there. On 1 March 1935, he sent the school a letter noting that his application had been pending for more than a year.