You’re sharpest in your 20’s; around 30, mental abilities begin to decline, particularly your ability to do maths. ___17___ Your vocabulary at age 45, for example, is three times as great as when you graduated from college. At 60, your brain possesses almost four times as much ...
2.形式复数实则单数(news, maths, politics, physics)。 3.形式单数实则复数(people, police, cattle)。 4.单复同形(sheep, deer)。 5.特殊变化(man—men, woman—women, foot—feet, tooth—teeth, child—children)。 6.国人变复数规律是:中日友好相一致(不变),英法联盟a变e,其余剩下加s。 7.以man...