A little practice with relatives  (based on ‘Xerxes Crosses...’ p. 228-9).

1)  Xerxes prepared a very great army, which he led (in)to Greece.

2) He ordered the soldiers to make a bridge, which a great storm (then) destroyed.

3) He ordered his slaves to punish the sea that ‘did wrong’. (use aorist of ἀδικέω)

4) He killed those who made the bridge = whose work made the bridge.  (both ways)

5) He watched the ships in which his army journeyed to Europe.