1．(2018·天津高考改编)It was only when the car pulled up in front of our house ________ we saw Lily in the passenger seat.
解析：that 句意：直到汽车停在了我们的房子前面的时候，我们才看到莉莉坐在乘客座上。此处是强调句型“It is(was)＋被强调部分＋that＋其余部分”，本句强调的是时间状语从句。
2．(2017·天津高考改编)It was when I got back to my apartment ________ I first came across my new neighbors.
解析：that 句意：正是当我回到公寓的时候，我第一次偶然遇见了我的新邻居们。此处为强调句型it's ...that ...，被强调的是句中的时间状语从句。
3．(2016·天津高考改编)You are waiting at a wrong place.It is at the hotel ________ the coach picks up tourists.
解析：that 句意：你等错地方了。长途客车是在宾馆接游客。去掉it is和空格处后是一个完整的句子，因此本句是一个强调句，填that。
