Complex Pronoun Case

Now here comes what could be considered a complex pronoun case.

Her little book was getting bigger.

Let's try another one together.

Cats need hats because of them.

Sorry, that's a simple case.

Their white hat was being overrun with bats.

That's much better. Here their stands in for cats and her for the girl. Without them those sentences would read:

The girl's little book was getting bigger.

And

The cats' white hat was being overrun with bats.

It is especially useful to use prepositions in this instance to avoid a bad case of the following.

The cats' white hat was being overrun with bats. The cats didn't know what to do so the cats did the next best thing the cats could. The cats froze.

Right, I see you're all probably sick and tired of the cat infestation right about now. In English though, you will want to make sure the pronoun agrees with the person that it is replacing, even in a lineup. The complex case would be considered a lineup because the nouns for people and things are modifying other nouns. Basically, it looks a big, long train car coupled up together. Think of it like this.

The cats have a white hat that protects against the bats.

That's all well and good of course. Then again, there is the other option of the two.

The cats' white hat protects against the bats.

See, I've already said what I needed in less than half the space. If I want to shorten my message even further, I could say:

Their white hat

When you do that though, be careful to introduce your replacing noun first for the person or thing. Otherwise, your sentence will sound something like this.

They are in the room.

Alright, what is in the room and who are they. Some people blame bad entities when really it's just a product of poor grammar. In other words, don't blame bad things for what you can do yourself. Let's try one more shall we? The best example is from the Scripture which reads:

And the two shall become one flesh.

Alright, you know just what to do. What can we replace and what shall we replace it with? Very good, alright. The two can be replaced with they. Although in this case I would advise against doing it, because then the sentence would become unclear. Then again, in some languages it is possible for all the pronouns and nouns in the lineup to agree in case. Then it would be determined by number and gender of the person or things discussed. Unless of course, the noun in the lineup was the most powerful of all and caused everything else to agree or fall into place. I would refer to common spoken and written cases in your language to show you how it's done. Don't forget to put the pronoun closest to the word it replaces. If not, it will sound a lot more like this.

Cats and bats eat hats. They are everywhere.

Right then, does they refer to the cats and bats or hats? Let's see that one more time, just for fun.

Cats and bats eat hats. I saw them, it's no lie.

First, who is them and second, whatever are they doing here of all places. Thirdly, where do they even go. At this point I don't know whether to give you an A and let you pass the class or sit you down and tell you kindly what you've done. Perhaps a little of both would be in order, then.