Sky darkens quickly.

Meaning: This means that the sky is becoming very dark, very fast. It's like saying, The sky is losing its brightness rapidly.

Choice of Words: Sky refers to the area above the earth where the sun, moon, stars, and clouds can be seen. Darkens means to become less bright or to lose light. So, "sky darkens" means that the sky is becoming less bright or losing its light.

Alternative Expressions

The sky is getting dark fast.

Meaning: This means the same as the first sentence, that the sky is getting darker quickly.

Choice of Words: Sky is the blue or black area above the earth. Getting is a verb that means to receive or obtain something. Dark means not bright. Fast means happening in a short amount of time. When you put them together, "The sky is getting dark fast" means that the sky is becoming darker in a short amount of time.

It's getting dark outside.

Meaning: This means that the area outside is getting darker, like when it's about to rain or get nighttime.

Choice of Words: It is a pronoun that refers to something that has already been mentioned. Getting is a verb that means to receive or obtain something. Dark means not bright. Outside means not inside a building or shelter. When you put them together, "It's getting dark outside" means that the area outside is becoming darker.

Related Expressions