If you don't have A maths and Pure Phy, it will be very hard to
catch up. My
friend almost got retained because he gei kiang, applied for H2
Physics while
he took combined science. My school retaining criteria is 2 H2 and
1 H1 Pass
only ler, and he almost got retained so you can imagine. But he did
A maths
during secondary level. So his H2 maths wasn't that bad. In JC, it
is very hard
to devote all your time for catching up, you still have H1 PW to
do. =( .
But if you want to take the risk or is hardworking enough, you
should try
because those two subjects are important to go into UNI, especially
H2
Maths.
Peace,
TB. 
