(someone's) heart is in (their) boots

if someone's heart is in their boots, they feel sad or worried.

His heart was in his boots as he waited for news of the accident.

• be easy on the eye
• be economical with the truth
• beef up
• beef up something
• been around
• been around the block
• been had
• been there, done that
• be every inch
• be every inch something
• be fair game
• be falling apart at the seams
• be far and away
• be far and away the best
• be far and away the [best/greatest/worst etc.]
• be far and away the greatest
• be far and away the worst
• be [faster/hotter/thinner etc.] than all get out
• be faster than all get out
• be fed sick to the back teeth
• be fed up to the back teeth
• be few and far between
• be fighting fit
• be fighting for life
• be fighting for your life