yet的用法When and where to build the new factory have not decid

口语上虽然可以这样说, 但主语太长了,(when and where to build the new factory整个当句子的主语) , 这种时候我们通常会用虚主词it来代替. 所以, 个人认为这样说比较好:
It has not decided yet that when and where they will build the new factory.
顺便补充yet的用法:
1. yet用作连词时,与but一样也主要用于转折,意为“但是”“而”：
例如: I have failed, yet I shall try again. 我失败了,但我还要尝试.
It is strange, yet it is true. 那真是怪事,然而却是事实.
2. yet有时可与并列连词and或but连用,构成习语and yet和but yet,且两者大致同义(均相当于表转折的but)：
例: I gave him ten pounds (and) yet he was not satisfied. 我给了他十镑但他仍不满足.
She’s vain and foolish, and yet people like her. 她很虚荣愚蠢,但人们却喜欢她.
3. although不能与表示转折的but连用,但是却可以与yet连用.
例：Although we have made some progress, yet we still have a long way to go. 我们虽然取得了些进步,但还是远远不够的.
4. yet作副词“还”,“仍然”讲
例: Much yet remains to be done. 尚有许多事情待做.
No one has yet seen an electron. 还没人见过电子.
5. 副词 yet 和比较级连用,作“还要”,“更”讲,常可用 even 代替
例: We must study yet ( 或 even) harder. 我们必须更加努力学习.
6. 副词 yet 用于现在完成时作“已经”讲,只用于否定句和疑问句中
例: Have you seen such a space shuttle yet? 你（已）见过这样的航天飞机吗?
注：在肯定句中表示“已经”要用 already,不能用 yet.若在疑问句中用 already 代替 yet,则表示惊异的语气.
例: Has the bell rung already? 铃真的打过了吗?