He seemed as if he ___ his homework when his mother came in.
After the equipment was introduced, they produced __________ machines this year as the year before.
Sweet memories __________ as I looked at the pictures __________ were taken at the beach last summer.
When the expression first came into being, people refused to use it but __________ they began to accept it.
Willie's wife never gives him pocket money until he __________ clearly how he will spend it.
Can you explain __________ the sun goes down in the west?