Everyone knows that _______ is dangerous to play with fire, but _______ is difficult is to prevent children from playing with fire.
| A．it, it | B．what, what | C．it, what | D．what, it |
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Unless you have planted something, you won7t be able to know the pleasure of watchintit _______
| A．grown | B．growing | C．to grow | D．to be grown |
.
Jim has_______so much weight that many of his clothes don't fit him any more.
| A．won | B．put | C．achieved | D．gained |
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Hardly_______when the fans began to scream with excitement.
| A．the star showed up | B．did the star show up |
| C．had the star showed up | D．the star had showed up |
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Tom_______at least three coffees every day until his doctor told him to limit it to one.
| A．had drunk | B．drank | C．has been drinking | D．has drunk |
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He is opposed to the project for the reason_______ it is not practical for the time being.
| A．why | B．what | C．because | D．that |