Commonly believe garden residents (4-3-3)

I believe the answer is:

adam-and-eve

I'm a little stuck... Click here to teach me more about this clue!

'commonly believe' is the definition.
'adam and eve' can be an answer for 'believe' (I've seen this before). I'm not sure about the 'commonly' bit.

I don't understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for adam-and-eve that I've seen before include "Eden couple" , "First couple on earth" .)

I've seen this clue in The Daily Express.

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