Chia động từ trong ngoặc cho phù hợp
----- Nội dung ảnh -----
20. When we (arrive) _______________ in London tonight, it probably (rain) _______________.
21. It (rain) _______________ hard. We can't do anything until (stop) _______________.
22. Last night we (watch) _______________ TV when the power (fail) _______________.
23. That evening we (stay) _______________ up to talk about the town where he (live) _______________ for some years.