It is filled with a kind of liquid whichthat gets frozen under 28 degrees.

A very subtle nuance between "that" and "which"
when you say "which" you are naming a property that the object possesses
when you say "that" you are identifying the object based on that property

Due to global warming, we must accept this crazy heat as a "new normal" thing in the summer.

I remember that I felt the same heat during my trip to Singapore several years ago.

The climate in Japan’s summer might have gottenbecome like that of Singapore.

To endure this heat, I need to take some additional measures to cool myself down when going out.

One of them is to use a neck cooler which has been frozen in the fridge.

It is filled with a kind of liquid which gets frofreezens under 28 degrees.

Its effect doesn’t last sovery long though.

Also, a parasol is also indispensable when walking on the street.

Here iIn Japan, we’ve been experiencing extremelvery hot days since June.

Due to global warming, we must accept this crazy heat as a normal thing in the summer.the increase in temperatures in the summer may be permanent.

It’s so hot and humid that. I feel as if I werelike Japan has turned into a sauna.

I remember that I had felt the same heat during my trip to Singapore several years ago.

The climate in Japan’s summer might have gotten likebe similar to that of Singapore.

In the past, it used to cool down after sunset or rain in the evening, but now it doesn’t, but now the heat persists.

To endure this heat, I need to takelook for some measures to coolkeep myself downcool when going out.

One of themstrategy I suggest is to use a neck cooler which has been frozen in the fridge.

It is filled with a special kind of liquid which gets frofreezens under 28 degrees.

It’s effect doesn’t last so long though.

Overall, I had better stay in a well air-conditioned room as long as possible.