Wish one could / be only too glad to (恨不得/巴不得)

Structure 恨不得/巴不得 + wished-for clause

Both introduce an intense wish followed by a full clause, but they divide the nuance. 恨不得 (hèn bu de) voices a vehement, almost always UNREAL or hyperbolic longing — something one wishes one could do but cannot: 恨不得马上飞回家 = "I'd give anything to fly home this instant". 巴不得 (bā bu de), by contrast, voices DELIGHT at something that can actually happen and that one craves: 巴不得早点放假 = "I can't wait for the holidays to start; nothing would please me more". Colloquial yet educated in register; both are followed by a verb or clause, never a bare noun.

Examples

听tīng到dào这zhè个ge消xiāo息xī，他tā恨hèn不bu得de马mǎ上shàng飞fēi回huí家jiā。
On hearing the news, he wished he could fly straight home.
孩hái子zi们men巴bā不bu得de早zǎo点diǎn放fàng假jià。
The children can't wait for the holidays to start.
工gōng作zuò堆duī成chéng山shān，我wǒ恨hèn不bu得de有yǒu三sān头tóu六liù臂bì。
With work piled sky-high, I wish I had a dozen hands.
你nǐ要yào是shì想xiǎng走zǒu，我wǒ巴bā不bu得de呢ne。
If you want to leave, I'd be only too glad.

Levels are indicative: they follow the standard Chinese Grammar Wiki (AllSet Learning) progression, not an official HSK 3.0 mapping. We never assign levels by eye.

This point and the other 370, with audio on every example, inside Wanyu.