Word formation
For questions 1-8, read the text below. Use the word given in capitals at the end of some of the lines to form a word that fits in the gap in the same line.
基础词:
Most of us assume that we laugh because something is funny, but research suggests that humour has surprisingly little to do with it. In one series of 1., researchers listened to everyday conversations and found that most laughter followed remarks that were not jokes at all. Laughter, it seems, is mainly a form of 2., a way of showing others that we are friendly. We are around thirty times more likely to laugh when we are with other people than when we are alone, a 3. that supports this idea. Laughter also appears to have 4. effects on the body. It reduces levels of stress hormones and may even increase our 5. of pain. Perhaps most 6. of all, real laughter is very difficult to fake. Listeners can usually tell almost 7. whether a laugh is genuine or forced, which may explain why forced laughter often makes people feel 8..