Choose the best answer to complete each sentence

giúp mk vs mọi người ơi mk đang cần gấp. Chiều mk phải nộp rồi
III. Choose the best answer to complete each sentence.
17. He fixed a metal ladder to the wall below his window_____ escape if there was a fire.
A. to  B. not to  C. so as not  D. so that
18. He sent his children to the school__________ get more knowledge.
A. for him to  B. to for them  C. so as for them to  D. so that he could
19. The workmen left red lights near the hole__________ warn motorists.
A. to  B. for them not to  C. so for them to  D. so
20. I am learning skiing at an indoor school________ when I get to Switzerland.
A. to skiing  B. to ski  C. so as not to ski  D. so that I can‟t ski
21. I am saving up_________ buy a helicopter.
A. due to  B. owing to  C. so as to  D. despite
22. He had the telephone installed in his car ______ his secretary to be able to contact him wherever necessary. 
A. so that  B. in order that  C. so as to  D. for
23. We built the roof with a steel slope________ the snow to slide off easily.
A. less  B. in order that  C. for fear that  D. for
24. The notices are written in several languages__________ to understand them.
A. for no one  B. every one  C. so that every one can  D. for every one
25. The policeman stopped the traffic every few minutes. He wanted the pedestrians to be across the road.  The policeman stopped the traffic every few minutes ____________
A. in order that the pedestrians can be across the road.  B. in order to the pedestrians be across the road.  C. so that the pedestrians could be across the road.  D. so the pedestrians could be across the road.
26. I am putting the nets over my strawberry plants_______ the birds can eat all the strawberries.
A. so that  B. in order that  C. for not  D. for fear that
27. We put bars in the lower windows____________ climb in.
A. so that every one could  B. in order that no one  C. for fear that no one  D. for no one to
28. Turn down the oven. We don‟t want the meat to burn while we are out.  Turn down the oven ________ A. for the meat don‟t burn while we are out.  B. not for the meat to burn while we are out.  C. so as to the meat not burn while we are out.  D. so that the meat can‟t burn while we are out