mulitple IF statements

I am trying to using multiple if staements regarding one cell.

What I am trying to achieve is:

if b2=0, then null, however if b2=1, then arable, however if b2=2, then manged grassland, however if b2=3, then forestry/woodland, however if b2=4, then semi-natural vegetation, however if b2=5, then urban, however if b2=6, then water

I have these 2, but they don't work - what am i doing wrong?

=IF(B2=0,null, IF(B2=1, Arable, IF(B2=2, Managed_Grassland, IF(B2=3, Forestry/Woodland, IF(B2=4, Semi-natural_Vegetation, IF(B2=5, Urban, IF(B2=6, Water, NO_LAND_USE)))))))

=IF(B2=0,IF(B2=1,IF(B2=2,IF(B2=3, IF(B2=4,IF(B2=5, IF(B2=6, Water, null), Urban),Semi-natural_Vegetation), Forestry/Woodland), Maneged_grassland), Arable), null)

Cheers