71. Do you still remember the farm (that) we visited three months ago?
72. The journey around the world took the old sailor nine months, during which the sailing time was 226 days.
73. There were dirty marks on her trousers where she had wiped her hands.
74. There are altogether eleven books on the shelf, of which five are mine.
75. Helen was much kinder to her youngest son than to the others, which, of course, made the others envy him.
76. As is often the case, we have worked out the production plan.
77. There was a time when I hated to go to school.
78. There are two buildings, the larger of which stands nearly a hundred feet high.
79. What surprised me was not what he said but the way he said it.
80. A fast food restaurant is the place where, just as the name suggests, eating is performed quickly.