等到 + Time/Event + 才/就 + Clause
The verb phrase 等到 (děngdào) means 'to wait until' a certain time or event. It combines 等 (to wait) with 到 (to arrive at), and is followed by a time expression or event clause. For example, 下一次要等到2040年 means 'the next time won't be until 2040.'
等到春天来了,我们一起去赏花。
Děngdào chūntiān lái le, wǒmen yīqǐ qù shǎnghuā.
When spring comes, let's go enjoy the flowers together.
等到他回来,我们再出发。
Děngdào tā huílái, wǒmen zài chūfā.
Wait until he comes back, and then we'll set off.
等到孩子上了大学,她才有时间旅行。
Děngdào háizi shàng le dàxué, tā cái yǒu shíjiān lǚxíng.
It wasn't until her child went to college that she had time to travel.