Event rate of long Gamma-Ray Bursts (GRBs) is expected to be an useful tracer of the cosmic star-formation history. For this purpose, it is necessary to understand what kind of star formations/galaxies are traced by GRBs. Here we report rest-frame far-infrared (FIR) continuum detections of GRB 070521 and 080207 host galaxies at $zsim2$ with ALMA band 8 and 9. The FIR photometries provide the reliable star-formation rates (SFRs), because FIR emission is free from dust extinction and possible radio contamination from long-lived afterglows of GRBs. The spectral energy distribution fittings indicate 49.85$^{+72.33}_{-2.86}$ and 123.4$^{+25.19}_{-21.78}$ $M_{odot}$ yr$^{-1}$ for the 070521 and 080207 hosts, respectively. The derived SFRs place them on the lq lq main sequencerq rq of normal star-forming galaxies at $zsim2$. The derived SFRs are significantly lower than that of radio observations. It is inferred that the observed radio fluxes in a previous study are contaminated by the afterglows. ALMA marginally detected [C~{sc ii}],158,$mu$m emission line from the GRB 080207 host galaxy with S/N $sim$ 4. This is the first detection of [C~{sc ii}],158,$mu$m of a GRB host at $z>2$, and the second detection among known GRBs. The luminosity ratio of [C~{sc~ii}],158$mu$m to FIR is 7.5$times 10^{-4}$, which is one of the smallest values among galaxies at $zsim 1-2$ with the same FIR luminosity. The lq lq [C~{sc ii}] deficitrq rq could be a new physical property to characterise GRB hosts at $zsim1-2$. Possible parameters controlling the deficit include the metallicity, initial mass function, and gas density.
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