The difficulty solving such a problem ten years ago was twice greater than________is today.
It is difficult for us to learn a lesson in life _____ we’ve actually had that lesson .
The rent is high , ____ the house is quite satisfactory .
At the age of fourteen , Betty went to a _____ girls’ school along with her sister .
Most people prefer _____ mony _____ it .
Cook was a strict but good captain , _____ who , usually , took care of the sailors on his trip .