第一节 完形填空（共15小题，每小题2分，满分30分）
阅读下面短文，掌握其大意，然后从1—15各题所给的A、B、C和D项中，选出最佳选项，并在答题卡上将该项涂黑。
The ups and downs of life may seem unpredictable. But scientists know there are clear 1 that almost all people share. Even if you’ve passed your “best”, you still have other 2 years to come. Certain important high-points come later in life.
When are you 3 ? From 18 to 25, according to I.Q. scores; but you’re wiser and more 4 with increasing age. At around 30, metal abilities begin to decline, 5 your ability to do maths. But your ability to complete other tasks 6 . For example, your vocabulary increases over time. At 60, your brain 7 almost four times as much information as it did at age 21. Because of this, some psychologists suggest that “maturity quotients” (M.Q.) be used to measure intelligence for 8 .
