Makes progress in trips below street level (7)
I believe the answer is:
strides
'makes progress' is the definition.
'strides' can be an answer for 'progress' (I've seen this in another clue). I'm not sure about the 'makes' bit.
'trips below street level' is the wordplay.
I cannot really understand how this works, but
'trips' could be 'rides' (I've seen this before) and 'rides' is found in the answer.
'street' could be 'st' (abbreviation) and 'st' is found within the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
'in' acts as a link.
Can you help me to learn more?
(Other definitions for strides that I've seen before include "Bags" , "Paces -- trousers" , "Takes great steps" , "Daks" , "footsteps" .)