I often have conversations with John over ______ telephone, while keep in touch with Tom by ______ letter.
________ for the fact that she broke her leg, she might have passed the exam.
His pale face suggested he ________ angry and I suggested that he ________ at once.
I ________ sooner but I didn't know that they were waiting for me.
According to the rules and regulations, all payments ________ be made in cash in the shopping center.
Look! There are so many mistakes in your composition. You ________ have fixed full attention on it.