swallow/take the bait

to accept something that is only being offered to you so that you will do something.

The offer of a free radio with every television proved very popular, and hundreds of shoppers swallowed the bait.

• on no account should someone do
• on no account should someone do something
• on occasion
• on order
• on own
• on own account
• on own head be it
• on own hook
• on own time
• on pain of
• on pain of death
• on pain of something
• on paper
• on person
• on pins and needles
• on principle
• on purpose
• on radar
• on radar screen
• on record
• on safe ground
• on schedule
• on second thought
• on second thoughts
• on shaky ground