A chemical reaction can change a substance into a solid, liquid, or gas. It may cause a substance to explode or could cause no change at all.
he could choke
some animals might not get what they need
It can cause skin cancer. It could also cause eye cataract.
If an organisms climate changed drastically enough it could become extinct, it just depends on the type of organism and the level of change, or it could mutate and assimilate to the new climate.
Some theories state that weather could change and others say that it could be the end of the world. No one is sure about this.
The word "could" implies a future possibility that might or might not happen.
Lots of things might happen in the afternoon. You might take a nap or siesta. You might have an after-school snack. You might play sports. It could be anything.
they might actually see an atom.
commitment
nothing will happen
A chemical reaction can change a substance into a solid, liquid, or gas. It may cause a substance to explode or could cause no change at all.
You might get hurt, or they might get hurt.
he could choke
The composition of the Earth's atmosphere (air) has changed over geological time. This change has been brought about by biological processes (life). The planets air is therefore part of the biosphere and any change in the air will be accompanied by biospheric changes.
A lot of things could happen. Nothing might happen, or the kittens could die, or the cat could die. Don't do it.
some animals might not get what they need