问题 make black boxes easier to discover的用法对吗

To make black boxes easier to discover under water, they can let out signals for 30 days.这个句子中的make black boxes easier to discover对吗，为什么不是通to be discovered。与make it easier to...这种用法有关吗？感觉不是一回事呢？

问题 to do做表语

尊敬的老师，有这样一句话: 背景:In the past 6 months he has made 5 trips. There were to Asia and two were to Europe.从背景可以看出这些trips已经做过了，为什么下面是 to Asia,不定式不是表示还未做吗？

问题 介词to后面为什么没有成分

Any problem that has something to do with teenagers' mental health is worth paying attention to. To后面为什么不加成分了呢？

问题 have most to中most何解？

While Europe’s monarchies will no doubt be smart enough to survive for some time to come, it is the British royals who have most to fear from the Spanish example."have to"本身就是必须的意思了，再加上most，“最必须”的意思，不太理解

问题 seem to be + 名词（ to be作的是表语吗，后面的名词有是什么成分）

问题 mean to say 的意思

"You don't mean to say you talked to him about her?" said Hughie.参考译文：你不会真的和他说了她的事。mean to do 在这是什么意思？

问题 to no avail语法正确

We searched the whole area but all to no avail. Robbie had disappeared.这里to no avail语法正确吗？all后面不应该要加are吗？然后to no avail 作表语？

问题 be used to用法疑问

It is in school that we meet, become used to, and learn to believe in the totally controlled society.老师好，请问这里become used to的宾语是不是少了？

问题 marginal to怎么理解

Thus, by the Devonian the land habitat marginal to freshwater was probably a rich source of protein that could be exploited by an animal that could easily climb out of water. 请问老师marginal to怎么理解，to表示什么意思？

问题 那这句话中是happened to meet是谓语

I happened to meet him. 有个短语是 happen to do sth 那这句话中是happened to meet是谓语？ him是宾语？还是说to meet做状语？

问题 due to做状语

due to是形容词短语， Their delay was due to the bad weather 但是如今也会看到当做状语用的 They delayed due to the bad weather。 还有单独用的， 这应作何解，它是不是一种非限定定语从句的省略，先行词是整个句子？

问题 too...to结构

It's not too late to turn back now.It's too early to know the outcome of her illness.以上两个句子，为什么it不是形式主语而是too...to结构？将其当作形式主语直接翻译为“现在想要回头不算太晚” 和 “现在要知道她的病情还太早”，这样也通顺...

问题 关于复合介词up to的用法

1. My blouse was rolled up to my shoulder. 这里动词是及物动词，up to这里是介词，是不是与rolled没有关系？ 2. 还有比如：he come up to this idea.这里可以不可以理解为come为不及物动词，up to看成介词？ 3. 像这种动词+复合介词应该...

问题 句子分析 to the extent that

Individuals identify themselves with their own group to the extent that any critical comment is taken as a remark which is rude to the individual as well as to the group. 请问老师to the extent “到某种程度”是作什么状语？that引导定语从句还是同位语从句？谢谢老师

问题 to one’s surprise的类似表达

英语中有个固定搭配是 to one’s surprise，意思是“令某人吃惊的是”。比如：To my surprise the door was unlocked. 使我吃惊的是门没锁。To my surprise he came ahead of time. 使我吃惊的是，他提前来了。To her surprise, she found her husband seated nex...