Input (grade 13): In the first part of the 1950s, the young Havel entered into a four-year apprenticeship as a chemical laboratory assistant and simultaneously took evening classes; he completed his secondary education in 1954.
Output (grade 10): In the early 1950s, the young Havel entered a four-year apprenticeship as a chemical laboratory assistant. He took evening classes at the same time and completed his secondary education in 1954.