All substances, ＿＿＿＿＿ solids, liquids, or gases, are made up of entirely atoms.
| A．whether they | B．whether | C．whether are they | D．whether are |
26. My suggestion _____ John should be sent _____his mother works is reasonable.
| A．that; in which | B．which; where | C．that; where | D．which; where |
25. The American Civil War lasted four years _____the North won in the end.
| A．after | B．before | C．when | D．As |
24. The task was difficult, but Helen’s _____expression let me know that she would not give up.
| A．determine | B．determining | C．determined | D．Determines |
23. I have two sisters, _____ working in this city.
| A．both of them | B．both of whom | C．and both of them | D．both of them are |
22. Was it _____the conference of APEC that made Shanghai the focus of the world then?
| A．holding | B．to hold | C．held | D．having held |