Introductory 'there'

[thehammer]

Should I use introductory 'there' in the following sentences?

1- How many types of rice are there found in India?
1a- How many types of rice are found in India?

2- There are 50 types of rice found in India.
2a- 50 types of rice are found in India.

3- How many types of fishes could you get in that market?
3a- How many types of fishes are there you could get in that market?

4- Many fish are available in that market.
5- There are many fish available in the market.

 

[Barque]

1 sounds wrong. 1a is all right.
Both 2 and 2a are possible. In 2a I'd start with "Fifty" and not "50".
3 is all right but I'd use "fish". 3a is wrong.
Both 4 and 5 are possible.

 

[Tarheel]

Should I use introductory 'there' in the following sentences?

1a How many types of rice are there found in India?
1b How many types of rice are found in India?

You don't need "there" at all.

 

[jutfrank]

This is a very hard and complicated question. You're essentially asking whether to use there be.

1- How many types of rice are there found in India?
1a- How many types of rice are found in India?

If you want to talk simply about what exists, you can use a there be question:

How many types of rice are there in India?

However, that's probably not what you mean. What I think you're asking is a question about agriculture and crops, and what grows in India. So a better question is:

How many types of rice grow in India?

2- There are 50 types of rice found in India.
2a- 50 types of rice are found in India.

If you're just talking about what exists, you mean: There are fifty types of rice in India.

3- How many types of fishes could you get in that market?
3a- How many types of fishes are there you could get in that market?

It's hard to understand what you mean here. I think you're talking about availability, in which case:

How many types of fish are available at that market?
How many types of fish can you buy at that market?

4- Many fish are available in that market.
5- There are many fish available in the market.

If you just want to talk about availability, I suggest you keep things clear and simple. To answer directly the two questions above:

Five different types of fish are available at that market.
You can buy five types of fish at that market.

However, you may also use a more complex there be phrasing here, if you want to place a focus on what exists as well as availability:

How many types of fish are there available at the market?
There are five types of fish available at that market.

It's useful to understand that there be sentences can express not just the existence of something but also the location of something.