We made plans for a visit but _____ difficulties with the car prevented it.
Our skin, if ______ to sunlight for a long time, can become darker.
_______ he met with the difficulty did he realize the importance of our help.
---How’s that? Who broke the glass? ---Well, it ______ me. I was doing my homework the whole evening.
Don’t be discouraged. ______ things as they are and you will enjoy every day of your life.
He kept a little notebook, in which _____ the names and addresses of his fiends.