pastw[7],
past[6], spat[6], pass[5], spaw[5], swap[5], staw[5], swat[5], ssaw[4],
pat[5], pst[5], pas[4], psa[4], sap[4], spa[4], pss[4], tss[4], paw[4], twa[4], wat[4], sas[3], swa[3], was[3],
pa[3], at[3], ta[3], ts[3], as[2],
