To describe the fact that the stock price suddenly decreased, you can say:
The stock prices just crashed.
To crash - In this sense it means to decrease suddenly and/or unexpectedly like a car crash.
He crashed on the sofa.
The price just plummeted.
To plummet - This means to also fall down suddenly like an apple falling from a tall tree onto the floor or a comet falling from space onto the earth.
The rock plummeted to the ground.
I hope that helps!
株価が急に下がった事実を述べるために、このように言うことができます。
The stock prices just crashed.
crash - この場合、まるで車の追突事故のように急に・予想外にガクッと下がったことを意味します。
例 He crashed on the sofa.
（彼はソファで寝落ちした。）
crash は少しカジュアルな印象があります。
The price just plummeted.
plummet - これも、まるでりんごが背の高い木から床に落ちるように、または彗星が宇宙から地球に落ちるように、急に落ちることを意味します。
The rock plummeted to the ground.
（岩が地面に落下した。）
参考になれば幸いです！
Hopefully you did not invest too heavily in these shares! We all know that share prices may go up or down...but when they go down it may be disastrous for some.
When the value of a share or the majority of shares drops sharply, there is a whole range of vocabulary that may be used:
A sharp drop
A rapid drop
Plunging prices
Plummetting prices
"Share prices plummetted on the London stock exchange today."
これらの株式にあまり投資されていないことを願っています。
株価が上下することはみんな知っていますが、暴落した時は人によっては大変なことになります。
株価又は大半の株が暴落した時に使える様々な語彙があります。
A sharp drop（暴落）
A rapid drop（暴落）
Plunging prices（株価の急落）
Plummetting prices（株価の急落）
Share prices plummetted on the London stock exchange today.
今日ロンドン株式市場で株価が暴落した。
1. The stock prices turn a sharp decline.
The word "sharp' means involving a sudden change. The word "decline" means a decrease in the value amount or quantity.
If stock prices took a sharp decline it means that prices were suddenly reduced.
1. The stock prices turn a sharp decline.
（株価が暴落する）
この"sharp"とは、急な変化を意味します。
この"decline"とは、価値や量が減ることを意味します。
もし株価が "a sharp decline" したら、株価が急落したことを意味します。
>The stock prices just dropped suddenly.
*dropped=fall
*suddenly=quickly and unexpectedly
......................................................
Example
Him: Hey, do you know what happened with the stock prices?
You:The stock prices just dropped suddenly.
.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.
>The stock prices just dropped suddenly.
株価は急に下落した。
*dropped=fall
落ちる＝落ちる
*suddenly=quickly and unexpectedly
突然＝急に、予期せず
例
Him: Hey, do you know what happened with the stock prices?
おい、株価がどうなったか知っているか？
You:The stock prices just dropped suddenly.
株価は急落したよ。
"There was a sharp drop in share prices." This explains that the price of the shares/stocks dropped/went down very quickly.
"The stock price just plummeted."
"plummeted" means it goes down very very fast.
There was a sharp drop in share prices.
株価が暴落した
株価が極めて短期間に下がったことを説明しています。
The stock price just plummeted."
株価が急落した
plummetedは、本当に短期間で下がるという意味です。
The stock price has plummeted dramatically in recent days.
The company's stock price dropped significantly in a short time.
The price of the stock fell suddenly in a small amount of time.
Words that can be used which can mean a price of something has gone down quickly and in a short amount of time, are "plummet", "drop suddenly", "fell", or "dove".
"The stock price has plummeted dramatically in recent days."
価格が急激に下がったことを表す場合、"plummet"、"drop suddenly"、"fell"、"dove" が使えます。
例：
The stock price has plummeted dramatically in recent days.
〔訳〕最近、株価が急落した。
My main stocks suddenly crashed...and I lost a great deal of my savings!
The value of stocks may go up and down in line with global market demands:-)
We allexpect to see some movement in share prices...but every now & then there is a "Black Swan Event" /an unforseen crash in the market. Stocks dropslike a stone!
"My main stocks suddenly crashed...and I lost a great deal of my savings!"
株式の価値は世界のマーケット需要によって浮き沈みがあります。株価の動きを期待しますが、ときには、 "Black Swan Event"（壊滅的被害） /an unforseen crash（不測の暴落）が起こることがあります。株は石のように落ちるのです。
"My main stocks suddenly crashed...and I lost a great deal of my savings!"
主要株式が突然暴落した。そして多額の貯金を失った。
イギリス 
カナダ 
南アフリカ 
アメリカ合衆国 
