39.3 Comparison Between 到 / 倒 dou2 and 咗 zo2
Both the verbal particle 到 dou2 (also written as 倒) and the aspect particle 咗 zo2 indicate that an action has been completed, but 到 dou2 emphasizes the success of completing the action. We often use 到 dou2 when the action is something that we weren’t sure we could complete, considering the situation. It can also be an action that we had failed to complete previously. Compare:
我上咗巴士。
ngo5 soeng5 zo2 baa1 si2.
I have got on the bus.
我上到巴士。
ngo5 soeng5 dou2 baa1 si2.
I was able to get on the bus.
[= I have got on the bus successfully.]
One possible situation to use 到 dou2 here is that the speaker wasn’t sure he or she could catch the bus before getting to the bus stop.
我買咗雞蛋。
ngo5 maai5 zo2 gai1 daan2.
I have bought eggs.
我買到雞蛋。
ngo5 maai5 dou2 gai1 daan2.
I was able to buy eggs.
[= I have bought eggs successfully.]
One possible situation to use 到 dou2 here is that the speaker wasn’t sure the supermarket was already closed before getting there to buy the eggs.