One by one, or the stream逐科购买，还是整组购买
The same three subjects, priced both ways. The right-hand column is what the stream costs; the difference is in the last column. 同样的三科，两种买法的价格对照。右侧为组合价，最后一栏是两者的差额。
| Stream组合 | 1 subject1 科 | 2 subjects2 科 | 3, one by one逐科买满 3 科 | Stream price组合价 | You save省下 |
|---|
Every subject in a stream is the full subject — the same practice sets, the same written explanations. A stream is a price, not a lighter version. 组合内的每一科都是完整科目——练习题组与文字解析完全相同。组合只是价格上的差别，内容不打折。
What a stream unlocks组合解锁了什么
Holding all three subjects of either stream opens the supplementary subjects — English, Geography, History and Combined Science — at a small price each. They cannot be bought on their own, at any price. 持有任一组合的三科后，即可加购辅修科目——英文、地理、历史与综合科学，每科价格很低。这些科目无法单独购买。
| Add加购 | Price each每科价格 | Two of them两科 | All four四科全选 |
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The Everything Pass全科通行证
Both streams, every supplementary subject, one code两个组合、全部辅修科目，一个启用码
Everything Pass
However much you add, this is the most you pay for that period. If your basket ever comes to more than the Pass, the order page swaps it for the Pass by itself — you never overpay by accident. 无论加购多少，同一期限内最多只需付这个价。若订单总额超过通行证价格，下单页会自动改为通行证——不会让你多付。
See it for your own subjects用你的科目试算
Tick three subjects and the stream price appears on its own. Tick more and the Pass takes over when it is cheaper. 勾选三科即自动套用组合价；继续加选，当通行证更划算时会自动改用通行证。
Where to next接下来