On April 1st, Mike decided to fool  his friends. At lunch time he said to Tom, "I think we're going to have a test this afternoon." "Test?" said Tom, "Really?" "Yes, it's quite true," said Mike. "When I was passing by Mr. Green's room, he was talking with another teacher about the test. Tell John, Rose and Joan about it." Later Tom told them about the test. Soon almost all the students knew about it. "How foolish they are!" he thought. When class began, Mr. Green said, "Class, we're going to have a test today." Mike was surprised. The test was too hard for him. After class, all his classmates thanked him very much. But he could only smile. "How foolish I was !"he thought. It really was April Fools' Day for Mike. Mike decided to fool his friends because   _   .
they were talking about the test they began to prepare   their lessons it was April Fools' Day they were foolish