To wrangle over an ass's shadow

I <u><em>stood up for him</em></u> when everyone else was criticising him.

To pull one's socks up

Who will <u><em>carry the day</em></u> in this war?

To live in clover

He knew she was dead but was completely <u><em>at sea</em></u> about the cause of her death.

To give one a long rope

To set one's face against

He <u><em>passed himself off</em></u> as a noble man.