One way to hold this is a bar magnet with iron filings on the paper around it. The filings do not spread evenly: they crowd at the two ends. Those two crowded points are the — the places where the pull gathers. The word keeps that picture wherever it goes, and the only thing that changes is how big the magnet is.
可以想成一塊條形磁鐵，紙上撒著鐵粉。鐵粉不是平均鋪開的，而是擠在兩端。那兩個擠得最密的點就是磁極——力量聚集的地方。這個字走到哪裡都帶著這個畫面，變的只是那塊磁鐵有多大。
登入就可以看每一支怎麼連回核心畫面。