Something is cost-effective when what you get out of it is clearly worth what you put in — good result, low cost.

what you get out of it你從它得到的東西 is clearly worth明顯對得起 what you put in你投進去的成本 when的時候， Something is cost-effective這件東西就是 cost-effective—— good result成果好、 low cost花費低。

The key point, and the one students miss, is that it does NOT mean cheap. A cost-effective machine might be expensive to buy; it earns the name because it lasts twenty years and saves money the whole time. So the word is about the ratio between cost and result, not about the size of the price tag.

The key point關鍵的一點， and the one students miss也是學生最容易漏掉的一點， is that就是： it does NOT mean cheap它「不是」便宜的意思。 A cost-effective machine一台符合成本效益的機器 might be expensive to buy買的時候可能很貴； it earns the name它配得上這個稱呼 because是因為 it lasts twenty years它能用二十年， saves money the whole time這一路都在省錢。 So所以 the word is about這個字說的是 between cost and result成本和成果之間的 the ratio比例， not about而不是 the size of the price tag價格標籤上數字的大小。

It belongs to business, government, and health writing: reports, proposals, meetings, budget arguments. In a report you will see 'a cost-effective solution', 'a more cost-effective way of doing this', and often the comparison that matters — 'cost-effective compared with building a new one'.

It belongs to它屬於 business, government, and health writing商業、政府和醫療的書面文字： reports, proposals, meetings, budget arguments報告、提案、會議、預算攻防。 In a report在報告裡 you will see你會看到 'a cost-effective solution'「符合成本效益的解決方案」、 'a more cost-effective way of doing this'「更符合成本效益的做法」， and often還常看到 the comparison that matters真正重要的那個比較——'cost-effective compared with building a new one'「跟蓋一座新的相比更符合成本效益」。

Note the hyphen: it is standard before a noun ('a cost-effective plan') and usual after the verb too ('the plan is cost-effective'). Some writers also use 'cost-efficient', which means much the same thing, though 'cost-effective' is far more common.

Note the hyphen注意連字號： before a noun放在名詞前面 it is standard是標準寫法（'a cost-effective plan'）， and usual after the verb too放在動詞後面也很常見（'the plan is cost-effective'）。 Some writers有些作者 also use也用 'cost-efficient'， which means much the same thing意思差不多， though不過 'cost-effective' is far more common常見得多。