English grammar problems, ask the master to explain them in detail!

Adverbial, where the verb infinitive phrase is used to indicate future behavior, thus meets the condition of the purpose adverbial, and if it is a definite, this expression should be used:

i need the key to opening the door.Indicates the key to open the door.

The infinitive phrase is used to say: I need a key to open the door, the semantics are different.

The 1870s is the subject and SAW is the predicate (meaning to witness).

No, it means the time, the 70s of the 19th century.

The anthropomorphism, the 1870s, the +adj denotes a type of person or thing. You are referring to the people of that era.

See means "witness" in English.

The subject at this point is usually time or city or country.

The testimonies are usually about major events or major changes.

For example, Shanghai Saw the 2010 World Expo

the late 1990s saw china's great changes.

Introductory word: that in which

Composition of the introductory word: no component, and because it does not make any component, it can be omitted.

The way these products are prosduced is ....The subject is obviously the way, and the predicate is the is the aftermath; Looking at the rest of the part, the subject these products, the predicate are prosduced, and the subject and predicate are complete, so it is also a complete sentence.

Originally, when the antecedent is way, the introductory word of the definite clause is in which that. For example: the way in which he looks at problems is wrong However, because that in which the sentence that leads these products are prosduced complete, that does not act as any component in the sentence, it can be omitted and not written.

Attach a flower to show your mood, don't spray if you don't like it!