单句语法填空 1.This is the theatre _______ we’ll visit a well-known pianist. 2.I still remember the night ______ she left the house. 3.I wish to thank Professor Smith,without ______ help I would never have got this far. 4.The scientist about ______ we are talking has gone abroad. 5.The ice on _______ you skate must be very hard. 6.The reason ______ she changed her mind is quite clear. 7.The days _______ they travelled together meant a lot to him. 8.I saw a house,the windows of ______ were broken. 9.The children,all of ______ had played the whole day long,were worn out. 10.The old man has two sons,and both of _______ are lawyers.