When you go outing with your sisters, you must see to ________ that they are safe.
— Pity you missed the lecture on nuclear pollution.— I ______ it, but I was busy preparing for a job interview.
. His stepmother is kind to him, ______ whom she has a deep love.
The naughty boy was muddy because he _______ soccer in the rain all afternoon.
Finishing their shopping at the mall, the couple discovered that their new car _______.
History is _____ simply memorizing dates, it’s about understanding the past.