ข้อที่ 15. Passage 2 Skimming is reading quickly ___14___. You can skim an article, a Web page, a newspaper, a textbook chapter, or a whole book. Why ___15___? You skim if you are in a hurry, have a lot to read, or ___16 ___ you read previously. You also skim to judge if certain material is worth reading. Here's on basic method of skimming: First, read the first and last paragraphs, or introduction and conclusion. Next read the first and last sentence of each paragraph ___17___, look for key words and read those parts. Above all, read quickly: ___18___ three to four times your normal speed. Don't try to comprehend more than about 50% ___19___ material. Don't try to understand details, and do not let unfamiliar ___20___.