UV-H2O2
photo-oxidation technology was only available for the advanced treatment of
low-turbidity water with a critical limitation of 6 NTU turbidity. H2O2光氧化技术适用于低浊度水的深度处理，降解效果以浊度6 NTU为分界点。请问老师这里的critical怎么理解？
...完成时的时间肯定是指向未来吧。2. By now all logic had gone
outof the window。这里用过去完成时的原因是什么呢？now似乎已经和过去时间完全没有关系了。3. Only time will tell if
the treatment has been successful.这里用现在完成时的原因是什么...
...; 我4句全填了had done结构，这样就不对吗？I'd rather he (left) earlier. （leave）I'd rather you (didn't speak) to him. (not speak)I'd rather my father (settled) the account. (settle)She'd rather you (didn't tell) anyone about it. (tell)
...be!(WALD) （02）Though they were brothers, the difference
between them was as great as could be.（DCAU） （03）They seemed as happy as can be when I last
saw them.（WALD） （04）Hillary works faster than was expected.(CDEG) （05）She's not as upset with them as might be
expected....
"You let us in or we'll break down this door!" He wondered if they were actually getting a ram of some sort to batter at the door. He was reasonably certain it would hold.He was reasonably certain it would hold. 是 be certain that 的结构吗？that 怎么可以省略呢？
...red his men to salvage as much as possible from the wreck.Nothing of value was found, but the numerous items which were brought to the surface proved to be of great interest.这里为什么不是which had been brought to the surface，如果不能，怎么辨别什么时候用过去完成式还是...
What are you doing outof bed, Tom? You’re ______ to be asleep. A. supposed B. known C. thought D. considered答案是 A，有人解释说 be supposed to 是固定搭配。但 be thought to 也是固定搭配啊。
Though he was very young, he knew how to behave well.倒装后是①还是②：① Young though he was, he knew how to behave well.② Very young though he was, he knew how to behave well.另外，③和④哪个是正确的？③ Though he was very young, he knew what the right thing was.④ Thoug...
...》中有这么一段话：He is much fish still and I saw that the hook was in the corner of his mouth and he has kept his mouth tight shut.The punishment of the hook is nothing. The punishment of hungry, and that he is against something that he does not understand, is everything.这里最后一句...
...，是不能和现在完成时态同用的，如我们不可以说 He has left two days ago. 为什么Maugham 在 Christmas Holiday 中又有It's bee n decided long ago that the only liberty worth anything is the liberty to do right 的说法呢?
...。She acts as an adviser to the president. 她担任总统的顾问。He was made president of the cricket club. 他被任命为板球俱乐部会长。4. captainHe was proud of being captain. 他因当队长而骄傲。The captain gave the order to abandon ship. 船长下令弃船。
... own business. If you will be so good as to turn your head slightly to the left, you will see the door. I wish you good-afternoon."请教老师： be so good as to do 这是一种什么结构？ 其中，这里的as是副词吗？ 起什么作用？可否省略as，即be so good to ？我不懂这...