on condition that引導的狀語從句（含虛擬條件句）

On condition that 可用于強調某人采取行動前必須事先認可的條件，通常位于主句之后，意思是“如果”“只要”“條件是”等。

一、連用陳述語氣

以下例句均出自詞典和語法書：

I will come on condition (that) she is invited too. 如果邀請她來, 那我就來。

You can go out on condition that you wear an overcoat. 你要穿上外衣才能出去。

I’ll lend it to you on condition that you bring it back tomorrow. 我把它借給你，條件是明天你還給我。

I’ll give you the day off on condition that you work on Satiny morning. 我讓你休一天假，條件是周六上午你上班。

1 will do it on condition that you help me. 只要你肯幫助我，我就愿做此事。

You can take my car on condition that you drive carefully. 你可以用我的汽車，只要你小心點兒開。

We’ll let you use the room on condition that you keep it clean and tidy. 我們可以讓你使用這個房間，條件是你把它保持整潔。

Shrewdly, he offered to provide financial backing on condition he became an equal partner. 他精明地主動提供財政支持，條件是他成為對等的合作伙伴。

二、連用虛擬語氣

這類虛擬語氣主要由 should + 動詞原形 構成。如：

He can use the bicycle on condition that he should return it tomorrow. 如果他明天能還回來，就可以借用這輛自行車。——摘自《薄冰高級英語語法》

I reluctantly agreed to a postponement on condition that the sale should be completed and the boat handed over by 31st August. 只有銷售事宜得以辦妥，并在8月31日前交付那艘船，我才勉強同意延期。——摘自柯林斯英語語法系列《連詞》