Miss Lee often (write) ... when she was on holiday. Tom (study) ... chemistry for 3 years and then he gave it up. My brother (join) the ... army when he (be) ... young

56. Miss Lee often ( write ) .............. when she was on holiday.
57. Tom ( study ) .............. chemistry for 3 years and then he gave it up.
58. My brother ( join )........the army when he ( be )...............young.
59. You ( receive ).............any letters from your parents yet ?
60. How long Bob and Mary ( be ) ............married ?