It took a long time for the connection between body temperature and illness ________.
30. More than 20 years ago he was badly wounded in the anti-Vietnam war. Since then he can only walk _____ an arm-chair .
29. Can you say _____ certain when he will come here?
28. He is too careful _____ his money; he never buys a drink for us.
27. You should write the first letter of the sentence _____ capital one.
26. I called _____ you last night, but you were out.