Original sentence: He completed his secondary education and took the Senior Cambridge examination at Raffles Institution in the top class in 1929 where he was a classmate of David Marshall, the first Chief Minister of Singapore; they became "great friends".Initially unemployed between 1930 and 1934 due to the Great Depression, he later worked for three years as a clerk in the law firm of Mallal & Namazie for a monthly salary of 20 Straits dollars, after which he joined the Government Clerical Services for 60 Straits dollars a month and was posted to the Official Assignee's office, which was in charge of administering the estates of bankrupt persons
Edited sentence: He completed his secondary education and took the Senior Cambridge examination at Raffles Institution in the top class in 1929, where he was a classmate of David Marshall, the first Chief Minister of Singapore; they became "great friends".Initially unemployed between 1930 and 1934 due to the Great Depression, he then worked for three years as a clerk in the law firm of Mallal & Namazie for a monthly salary of 20 Straits dollars, after which he joined the Government Clerical Services for 60 Straits dollars a month and was posted to the Official Assignee's office, which was in charge of administering the estates of bankrupt persons