Please help! Can anyone speak japanese?

Question

I need to convert these few sentences to Japanese:

I think they are good for mountain climbing

What's the biggest lake in Japan?

What's the population of Japan?

Answer 1

1: kore ga tozan no tame ni tsukattara ii to omoimasu.

これが登山のために使ったらいいと思います

2: nihon no ichiban ookii mizuumi wa nan desu ka?

日本の一番大きい湖は何ですか？

3: nihon no jinkou wa nan desu ka?

日本の人口は何ですか？

Answer 2

I think they are good for mountain climbing

これらは、登山に適した道具です。

korerawa tozan ni tekishita dougudesu.

What's the biggest lake in Japan?

日本一の湖は何ですか？

nippon ichi no mizuumi wa nandesuka?

What's the population of Japan?

日本の人口は？

Nipponno jinkou wa ?

Answer 3

I think they are good for mountain climbing

これらは 登山に上手道具です。

Korera wa tozan ni jyouzu dougu desu.

You can add a few end particles if you want more emphasis

yo- makes it an exclamation-like

zo- makes it more firm

na- sort of like ne, for men, it's where you want agreement

ne- looking for agreement

wa- like yo, for women.

What's the biggest lake in Japan?

日本一の湖は何ですか？

Nihon ichi no mizuumi wa nan desu ka?

What's the population of Japan?

日本の人口はどれぐらいですか？

Nihon no jinkou wa dore gurai desu ka?