See: from the sublime to the ridiculous

• holy smoke
• home away from home
• home free
• home from home
• home in
• home in on
• home in on something
• Home is where the heart is.
• home straight
• home stretch
• home truth
• honest to God
• honest to goodness
• honest-to-goodness
• Honesty is the best policy.
• honeymoon period
• hoof it
• hook, line, and sinker
• hook up
• hook up with
• hook up with someone
• hope against hope
• hope chest
• hop into bed with
• hop into bed with someone