一塁[ichirui] first base
一塁手[ichiruishu] first baseman
一塁線[ichiruisen] first-base line
堅塁[kenrui] stronghold
三塁[sanrui] third base

三塁手[sanruishu] third baseman
三塁線[sanruisen] third-base line
三塁打[sanruida] three-base hit
出塁[shutsurui] on base (baseball)

に就て[nitsuite] concerning
に就き[nitsuki] because of
去就[kyoshuu] committing one's self
就いては[tsuiteha] in line with this
就きましては[tsukimashiteha] in line with this

就く[tsuku] to ascend (the throne)
就ける[tsukeru] to install (a king, emperor, etc.)
就学[shuugaku] entering school
就学義務[shuugakugimu] compulsory school attendance
就学児童[shuugakujidou] school child