  Since January 1997, we have monitored 15 GRB fields, detecting 6 optical/IR
afterglows. For GRB 970508, we derive a power-law decay exponent alpha = -1.19
(R-band). The luminosity of the host galaxy L relative to the characteristic
luminosity L^{star} is in the range 0.06--0.15, i.e. a dwarf galaxy. For GRB
980326, we derive a power-law decay exponent alpha = -1.7, taking into account
the new upper limit for the host as R > 27.3 provided by Bloom and Kulkarni
(1998). This implies one of the fastest GRB optical decays ever measured. The
fact that only about 50% of optical transients have been found within the
gamma/X-ray error boxes, suggest that either considerable intrinsic absorption
is present or that some optical transients display a very fast decline. We also
propose that the secondary maximum detected on 17 Apr 1998 could be explained
in the context of the SN-like light curves 2-3 weeks after the GRB, as recently
suggested by Woosley (1999).
