1．(2018·天津卷改编)It was only when the car pulled up in front of our house that we saw Lily in the passenger seat.
2．—How was it that you improved your work efficiency so much?
—Oh, we have introduced some modern equipment.
3．(重庆卷改编)Bach died in 1750, but it was not until the early 19th century that his musical gift was fully recognized.
4．(天津卷改编)You are waiting at a wrong place.It is at the hotel that the coach picks up tourists.
