【推荐1】One of the main reasons for this is ________ teachers work too hard but get too little.（用适当的词填空）

【推荐2】单句语法填空
1. Exactly ________ the potato was introduced into Europe is uncertain, but it was probably around 1565．
2. It shocked the world ________ the United States withdrew from some major agreements it had been committed to, including the 2015 Paris Agreement on climate change and the 2015 Iran Nuclear Deal．
3. I need help now! I have to fix a leaking pipe in my bathroom but I’m not sure ________ to begin．
4. Forty grams of meat per day is ________ people should consume in order to stay fit．
5. The famous player tried again and again after each failure．That's ________ he succeeded at last．
6. The retired engineer is showing ________ the wheelchair climbs stairs, which all the curious visitors want to know．
7. It hasn’t been made clear ________ the new underground line is to be open to traffic．
8. The problem is ________ sometimes when we are given something on a constant basis, we start to take it for granted and forget to be thankful for what we already have．
9. Ten percent of life is ________ happens to you and ninety percent is ________ you respond to it．
10. After a day’s exhausting climb we arrived at ________ we had been told was Garden in the Air．
11. Sometimes, ________ we show our gratitude to a person is reflected in the kind of food we serve him or her．
12. It remains to be seen ________ this plan is practical enough to keep the project going．
13. Some summer camps can provide you with as many as ten courses, and you are required to choose ________ suits you best．
14. It is reported that a huge percentage of bird species are in danger．It's ________ their habitats or homelands are disappearing．
15. I just wonder ________ it is that all the villagers think highly of him．
16. If you leave this application form and go to another website, you will lose ________ you have already filled out on this form．
17. ________ they’ve managed to get everything finished so quickly is not clear to us．
18. A proposal was put forward at the meeting ________ the new cement plant shouldn’t be built near the school．
19. The most exciting moment was ________ I was given the first prize．
20. They are discussing the problem ________ they should stop investing money in that project．

【推荐3】The reason ___________ I can’t put up with her is ___________ she’s interested in nothing but shopping.